The Tower's north doors shook as some tremendous force struck them from outside. Doors that had required two men each to move shuddered and rattled on their massive steel hinges like window shutters in a hurricane, making everyone in the hall jump in alarm and terror. “What in the name of...” began Balvern.

Before he could complete the sentence the doors shuddered to another blow even mightier than the first, and that was followed by a third and a fourth, a regular pounding as something was hammered against the doors from outside. “They're using something as a battering ram!” said Amberley. “Something heavy...”

Captain Machett edged warily to one of the tiny peepholes in the doors, ready to jump back if there was a Radiant there waiting to cast a curse on him. He put his eye to it, watched for a moment, then jumped back, his face red with outrage. “The Greene Cannon!” he said, spitting the words like a curse. “They're using the Greene Cannon!”

Everyone in the hall shared his fury. Of course, there was nothing else it could have been! The Greene Cannon was one of the very first cannons to ever be made, shortly after the invention of gunpowder, and had been used by Field Marshall Montgomery Greene to deliver a decisive victory against the armies of Belaxia two hundred years ago, when Marboll had been a regional capital of Carrow. Ever since then, the cannon had been on display in Victory Park, two miles to the west. A war memorial and a tourist attraction on which half raised animals had climbed and on which pigeons had left their droppings.

The art of metallurgy had been in its early days back then. Steel had been brittle, less resilient than the metal used to make modern artillery, which meant that the Greene Cannon had had to be three times the size and weight of a modern cannon hurling a ball of the same size. A modern cannon, used as a battering ram against the north doors, would have taken all day to break through them. The Greene Cannon would be able to do it in much less time. “This is an insult!” cried Machett, his hands balled into fists by his sides. “A deliberate humiliation! To use a symbol of one of our greatest victories as a weapon against us...”

“It really doesn’t matter what they use to kill us with,” replied Amberley. “They probably don't intend for it to be a humiliation. For them, it’s probably just the most convenient tool.”

“Is that supposed to make me feel better?”

“It's still going to take them a while to break through,” said a member of the Tower garrison. “Those doors are eighteen inches thick!” He kept glancing over at the King as if he couldn’t believe they were going to die together. He, a common soldier, and the King! His face was glowing with pride as if he couldn't imagine any greater honour. “We've probably got hours yet...”

Even as he spoke, another tremendous blow struck the doors, and this one caused the bolt at the top of the left hand door to burst out of its mounting with a shower of tiny chips of stone. Freed from its restraint, the top of the door was visibly pressed inwards and a groan came from the huge timber barring them closed, along with an audible crack as something began to give. The next blow caused the bottom left bolt to shift, one of the mountings pulling half an inch from the wall, and another cracking sound came from the timber. “It's not the strength of the doors themselves that matters,” said Amberley matter of factly. “It’s the strength of their hinges and mountings.”

“Brace them!” ordered Leothan. “Find something to brace them with!”

“What with?” asked Amberley. “Tables and chairs? There's nothing here that’s anything like as strong as what's already holding the doors in place.”

Leothan could only stare at him. “I had no idea they'd get through so fast!” he said.

“None of us did. It never occurred to anyone that they might... At least there’s only one Greene Cannon. They'll be using lesser means to get through the other doors, which means this is where they’ll get in first. Majesty, I must now insist that you retreat further into the Tower.”

“Why? Once they're in, they’ll sweep through every level of the tower, root us out wherever we hide. I'm staying right here. I'm going to face them when they break through, and I'm going to get Radiant blood on my blade before I go down.”

His inspiration gave heart to the others. Men whose courage had been wavering found the strength to stand firm, and hands clutched weapons with new determination. “It's been a great privilege to have ruled over such fine people!” said Leothan, fighting to keep his voice from breaking with emotion. “Helberion is the greatest country in the world. What we’ve achieved will awe and astonish the rest of the human world when they hear of it, and our final end will not detract from that. This is our end, that is certain now, but it will be such an end that, no matter what happens after this, this moment will live on in history for as long as mankind survives! And when history fades, we will live on in legend and folklore! Today, we become immortal!”

To his surprise, a cheer rose from the other people on the hall. “Three cheers for King Leothan!” cried Amberley, brandishing his sword above his head. “The greatest King ever to have worn a crown!” The hall shook with the cheers that rose in reply, and to their astonishment there was a pause in the blows shaking the doors. They all fell silent as the assault faltered and Machett took a chance, running back to the peephole to take a quick glance outside. “They're just hanging there!” he said, laughing as he ran back to safety. “In think the cheering surprised them! They don't know what to make of it!”

A moment later, though, the door shook to another blow as the assault resumed. “Looks like they’re over it,” said Amberley. “Ballista crews, the moment you get a clear shot at a Radiant, take it. Don’t wait for the order. Then reload as quick as you can. The record is forty three seconds. I expect you to beat it.” The crewmen nodded back, and the men holding the smouldering tapers edged closer, ready to light the bolts.

The right hand door was holding firm, but both the top and bottom bolts of the left hand door had failed and it was now being held closed only by the bar, which now had a noticeable bend to it. Splinters were breaking out in the middle, looking like the fangs of some wild monster that gaped wider with each new blow. The sound of piping could also be heard as one of the Radiants came closer to the doors. The sound rose in pitch, and then momentarily stopped before resuming at its customary low tone. It had just cast a curse, they knew, on the off chance that there was someone within range on the inside.

The next blow momentarily pushed the door far enough in that the creature was able to push the tip of a tentacle through in an attempt to lift the bar. Someone shot an arrow at it. The tentacle tried to pull back but it was held fast by the door closing on it. It had to wait until the next blow from the Greene Cannon before it could free itself. Several of the defenders chuckled at the faintly ridiculous sight, and Leothan hoped it had hurt the creature, even if only trivially.

The light hearted moment was soon forgotten, though, as the next blow caused the loudest crack from the bar so far, a crack that allowed it to bend considerably. This is it, thought Leothan. The next blow, or the one after that, and they’ll be through. He glanced at the ballista crews, standing tense and alert. “You, the crew on the left,” he said. They looked across at him. “You hold fire. Let the other crew fire first. There's no point in you both hitting the same creature. Crew on the right, you hit the first Radiant to come through. Crew on the left, take the second one. Also, wait until they’re actually in the tunnel. Maybe we can block it with their corpses.” They both nodded. Amberley leaned closer to the King so he could whisper quietly to him. “They're called crews one and two,” he said.

“Right,” said Leothan with a rueful grin. “I'll remember that for next time.”

Another blow hit the door, and the bar finally gave way, the left hand door flying open to admit the Greene Cannon, hanging suspended in the tentacles of three Radiants. The dropped it onto the drawbridge with a loud crash and the creature that had been loitering just outside launched itself forward on its thickest tentacles. There was a thud from ballista two and the bolt flew, flames trailing from its tip. It struck the Radiant cleanly in the buoyancy sacks and it burst into red fire. Leothan’s arm flew to cover his face as a wave of heat swept over them, and when he looked again the other Radiants were already dragging their fallen comrade away by pulling on its trailing tentacles. A second Radiant lurched forward and the second ballista bolt flew, causing it to also explode in flames.

The two crews hurried to reload their weapons, but the Radiants were already clearing the tunnel again and a third was preparing to enter. Its piping was rising as it prepared to cast a curse, and this time everyone in the hallway would be in range. Leothan knew he only had seconds of humanity left and he decided to make the best use of them. He ran forward to the sound of gunshots as soldiers fired at it, swung his sword as hard as he could at the nearest tentacle.

The blade cut cleanly through the luminous flesh, spraying him with green blood, and the creature spasmed. The King prepared to strike again, but someone had grabbed his arm and was pulling him back, away from the creature. Leothan shook him angrily off, then prepared to make another lunge at the creature, but he stopped, frozen in astonishment at what he saw.

The Radiant appeared to be having some kind of seizure. Its body had landed on the floor, its tentacles no longer able to support it as they thrashed wildly at the air around it. It looked comically as if it were trying to drive away an attacking swarm of wasps! “What’s wrong with it?” he demanded.

“Maybe one of the arrows hit its brain or something,” said the member of the Tower garrison who'd pulled him back to safety.

“We tried that, didn’t we? We decided that their brains were distributed throughout their bodies. Not all in one place, like ours are. Something like that. Isn't that right, George?”

Ballista crew two, meanwhile, had finished reloading their weapon. “Back away from it!” shouted the Sergeant, and he then pulled the trigger. The flaming bolt flew and the agonised creature burst into flames. The other ballista crew finished reloading their weapon a moment later and prepared to shoot at the next Radiant to try to enter, but the doorway remained empty.

“Someone tell me what's happening!” demanded the King.

“Don’t know,” muttered Amberley. He tried to edge his way towards the door to see out, but the flames of the burning Radiant were too hot. Fortunately the fire began to burn low very quickly, and then Machett edged carefully past it along the tunnel until he could see through the open door. “They're leaving!” he said in amazement.

“What do you mean, leaving?” said Leothan, thinking he must have misheard.

“They're all up in the sky, all of them! Not just the ones attacking us, all the Radiants in the city! They're all leaving! Fast!”

Leothan went to join him, stepping out onto the drawbridge, where he was joined by the others. He was right, the King saw to his astonishment. The sky was full of Radiants, apparently gaining as much altitude as they could and summoning a gale to carry them out of the city. “What are they doing?” asked Balhern. “They'd won! Why are they going?”

“Where are the scientists?” asked Leothan as a glorious possibility occurred to him.

“I send a man to fetch them. They should be here, in the Tower somewhere.”

“Did you see them get here?” He turned to Machett. “Did you see them arrive?”

“Well, no, but things have been so crazy...”

“We have to get to their lab! Now!” He hurried towards the carriages, but Balhern and his men ran to overtake him and the head guard held his hand out for the King to hang back while he checked to make sure it was safe. “Clear,” he said after a moment. “No enemies.”

The King stared up at the departing Radiants, now nothing more than tiny motes of light, just visible above the wall. The air was fresh and cool and he breathed in deeply, his whole body trembling as the adrenalin rush began to wear off. The carriages were still intact, he saw, although the horses had been unhitched and had long since fled. They would still be in the Tower grounds somewhere, though. It probably wouldn’t take long to find them and get them hitched up again. “Get these carriages ready to move out as soon as humanly possible!” He ordered.

“The Electric Messiah!” said Amberley as men ran off to obey. “Is that what it is?”

“Let's go find out!” said the King.

☆☆☆

Shanks stared in astonishment as the Radiant thrashed and danced wildly just a few yards away from him, giving every appearance of being in unbearable agony. Its piping had risen to a continuous, almost inaudibly high pitch that sounded to the scientist like a scream, a scream that just went on and on and on. Shanks’ hand was still on the main switch that was delivering power to the experimental alternator, and he stared at the apparatus in dawning wonder. Was it working? Was the apparatus he and Andrea had spent so long working on actually working, delivering the mysterious side effect that so tormented the creatures? He noted that there was a bright arc of electricity between the two graphite contacts, an arc that had a barely perceptible flicker as if it were coming and going almost too fast to see. It was alternating! he realised! The tuning circuit was working, causing the current flowing across the contacts to change direction nearly a hundred times a second! “We did it, Sophie!” he said, his voice hushed in awe. “We did it! You should have seen this! And you too, Andrea!”

A series of heavy thumps came from the Radiant as one of its tentacles pounded the floor hard enough to split its skin and spill green blood onto the tiled floor. It was trying to get away, he saw, but it seemed to be having trouble finding the hole in the wall it had come in through. A sudden fear came over him as he realised that it could destroy the machine with a single blow from the smallest of its tentacles. Why didn't it do that? It was almost as though the alternator was tormenting it so much that it was literally incapable of rational thought! Incapable even of delivering the simple blow that would still have given the Radiants victory and meant the end of human freedom across the whole world! It could still destroy the machine by accident, though. A wild spasm could still bring a tentacle crashing down on the apparatus at any time! Shanks took hold of the table, therefore, and tried to pull it away from the tormented creature.

It screeched as its legs scraped across the floor, but he'd only moved it a couple of inches before the apparatus wobbled and swayed, coming within a hair of toppling over and crashing to the floor, to the ruin of all mankind. He let go of the table and grabbed hold of the nearest support scaffold, holding it steady. At the top the upper coil wobbled, and he stared in terror at the clamp holding it in place. If he'd failed to tighten it enough, the coil might slip from its grasp and fall to the table... The wobble stopped and he breathed a sigh of relief, letting go of the scaffold and stepping gingerly away from it. Forget about moving it! he told himself, but the Radiant was still so dangerously close, still thrashing wildly...

The thrashing stopped and the Radiant just sat there for a moment, trembling as if a current of electricity was passing through it. Its eyes were staring at nothing, wild with madness, as if the agony it was suffering was so great that it had destroyed its very sanity. Then, with one last shudder, it collapsed, its tentacles suddenly losing their ability to support it. Its eyes low their focus and it settled onto the floor, sagging, going limp, until it resembled a jellyfish washed up on the shore. It then lay still, except for one last tentacle that continued go twitch for a moment or two longer before also falling still.

It was impossible to tell if it was dead, but it no longer showed any signs of life and Shanks allowed himself to hope that the device he'd helped to create had somehow killed it. The assault on the building from the other Radiants outside had also stopped. There was a ladder standing in the corner, used while replacing the charcoal contacts of the electric candles in the ceiling, and he moved it to stand below one of the surviving windows. Then he climbed it and looked out.

There were no Radiants in sight. The entire city seemed to be deserted and empty, the only movement being fallen leaves and small pieces of litter blowing along the street below. His heart soared with joy. They'd done it! They'd created the Electric Messiah! The machine that would be the saviour of mankind! With it he would avenge the destruction of his people's civilisation, three thousand years before!

He went back to the machine, where he checked that the steam pump driving the cooling water had plenty of fuel, and prepared another couple of batteries for when the first one began to run out of power, which it would very quickly. Then he just stood there, staring at the flickering spark passing across the graphite contacts, savouring the accomplishment, wishing that Sophie Bellhine and Andrea McCrea were there to share the moment. He was still standing there when King Leothan and the other defenders of Marboll Tower entered the room a few minutes later, to stare in astonishment at the dead Radiant and the machine that appeared to have killed it.

“Is that it?” said the King, staring at the machine. He was trembling with excitement and relief and grinning in a most un-regal way. Having resigned himself to personal death, not to mention the end of his whole kingdom, the realisation that the end might not be coming after all was leaving him a little light headed. “You did it? You built the machine?”

“Yes,” replied the inventor, without turning to look at him. He remained staring at the machine, his back to the King. A serious breach of etiquette that made the other members of the King's retinue frown with disapproval. “We built the machine. It sent that creature mad, then killed it. The others seem to have just been driven away, because they were further away, I assume. Whatever emanates from this machine seems to get weaker with distance.”

The flat, emotionless tone of his voice told Leothan that something was seriously wrong, though, and it wasn't hard to figure out what it was. “Where's Andrea? he asked.

Still Shanks didn't turn. “She... She didn't make it.” He turned his head to a pile of scattered clothing in the middle of the room, then returned his gaze to the flickering electric spark.

Leothan stared, then walked over and put his hand on the man’s shoulder. “I'm sorry,” he said. “She was an exceptional woman.”

“Can you build the machine without her?” asked Amberley.

“George!” snapped the King angrily. “Some tact, please!”

“I’m sorry, Sire, but this is a matter of the most urgent national security. If the survival of our nation depends on the production of these machines, then we need to know if we have someone who actually knows how to build them.”

“We already have a functioning machine. I assume any reasonably competent engineer would be able to duplicate it. Is that right, Mister, er...” The King realised to his embarrassment that he couldn't remember the man's name. Darnell hurried over to whisper in his ear. “Mister Shanks.”

“Yes,” replied the scientist, his voice still flat with grief. “Certainly.”

“Mister Shanks,” said Leothan, “What happened to Andrea McCrea was terrible, but the Kingdom is still in danger. I know you're grieving, as are we all, but there is still work to be done. I need you to build more of these machines, as many as you can. Whatever you need, just let me know and it will be provided. We have to get them to the other cities of the Kingdom before the Radiants decide to attack them instead. Can you do that?”

Shanks finally turned to face him. “Yes. I’ll do it. I'm sorry I... I'm sorry I didn't...”

Leothan waved it away. “I’m going to summon as many engineers as I can find and bring them here. You will teach them how to build these machines. We have to spread this knowledge as widely as we can, as fast as we can. Finally, I need you to write down a series of instructions that can be sent by telegram to scientists in other countries, telling them how to build these machines...”

“Majesty!” cried Amberley in shock. He got a grip of himself and spoke with more self control. “Your Majesty, this machine clearly gives us a significant tactical advantage over other countries. It should be kept highly secret, every measure taken to ensure that the secrets of its construction don't leak out!”

“Not this time, George. This isn't a war of one human country against another. It's a war of humans against Radiants. If all other human nations succumb to those creatures, it’s only a matter of time before we fall as well, no matter how many of these...” He broke off and turned to the scientist. “What is it called, this machine?”

“We've just been calling it an alternator. I suppose a more accurate name would be an arc oscillator.”

“Alternator will do.” He turned back to the Field Marshall. “The Radiants can easily do to us what they did to Carrow. Cause a draught, cause our crops to fail. Invading another country to survive, as the Carrowmen tried to do, will not be an option if there are no other countries. That is why we have to disseminate this machine as widely as possible. We won't survive unless everyone survives.”

“Your Majesty,” said Shanks, “I should point out that this machine has many other applications. It will transform any society that possesses it, that's why we were trying to invent it in the first place. The long distance transmission of electricity, new forms of communication. It could even form the basis for new kinds of weapons, the nature of which we can't begin to imagine yet! The Field Marshall is right to be concerned.”

“Thank you for telling me. Nevertheless, my orders stand. Make sure Kelvon is the first country we give it to. Then Carrow.”

“Your Majesty!” This time the Field Marshall made no attempt to hide his dismay.

“Carrow,” confirmed the King, giving him a sharp look. “They have more reason than most to fear the Radiants.” He turned to Darnell. “Is the telegraph link to Charnox still intact?”

“It was the last I heard, Sire.”

“Arrange for a message to be sent to King Nilon. Tell him everything that's happened here. The destruction of his army, the rout of the Radiants. Tell him that we're on our way to arrest him, and that the continued life and health of my daughter is the only thing that will save him from the gallows.”

“Your Majesty, the deadline he gave us has long since expired. He said he would...”

He couldn't finish the sentence, but the King nodded nonetheless. “We have to hope that he decided to extend the deadline, to keep the pressure on us. Send the message, Peter.” Darnell nodded and gestured for one of the runners to obey.

Balhern and one of his guards had been talking, meanwhile, and the head guard was looking increasingly concerned. “Is something wrong, Balhern?” asked the King.

“It's nothing, Sire,” relied the head guard.

“It doesn’t look like nothing. It looks as though something's bothering you.”

“Just something one of my men said to me, Sire. I'm sure it’s nothing.”

“This is currently the most important room in the world, Balhern. Nothing in here is nothing. If there's something here that's bothering you, we need to know what it is.”

“Yes, Sire. Well, perhaps Manner should tell you himself, Sire.” The guard shook his head in terror, but Balhern waved him forward. “Tell the King what you told me,” he commanded him.

Everyone was staring at him expectantly and he wilted nervously under their gazes. “Well, Sire,” he began hesitantly. “You see, before I began working in the palace, I was a detective in the city guard. When you enter a crime scene, you have to examine everything in it, try to work out what happened in it. It became such an ingrained habit that I still do it whenever I enter a room where something's happened, like this one.”

“And what do you think happened here?” asked the King.

“Well, it’s pretty obvious for the most part,” said the guard, gaining confidence. “The Radiant broke in through the window. It cursed the lady scientist, the other scientist turned on the machine which killed the Radiant...”

“And?” prompted Leothan.

“Well, Sire, no matter how I turn things over in my head, I can't see how this chap here...” He gestured towards Shanks. “...avoided being cursed as well. We have a pretty good idea what their cursing range is now, and the machine is well inside that range from where the creature is now. The creature can’t have moved here after he turned the machine on because it came down through that hole in the wall, which is directly above it. The lady scientist can't have turned the machine on just before she got cursed because her clothes are way over there. The man must have turned it on, and he must have done it while the Radiant was right there, easily close enough to curse him.”

“So how is he still human?” asked Balhern, eyeing the scientist suspiciously.

Leothan relaxed in relief, but noted that Shanks was staring at him in alarm. We need him, he told himself. I have to reassure him, let him know that neither he nor his people have anything to fear, or he'll be too distracted to do what he has to do. “It's not something you need to worry about,” he said, therefore. “Thank you for bringing your concerns to my attention, but it’s of no importance.”

“With respect, Majesty,” said Balhern. “If this man has found a way to protect himself from a Radiant’s curse, he needs to share this information with the rest of us.”

“It's not something that can be shared, Balhern. Be reassured that I already know the man's secret and I'm happy for him to keep it. Now put it out of your head, that's an order.”

The head guard nodded, noting that Amberley and Darnell were both carefully averting their eyes from him, telling him that they also knew the man’s secret. Very well, he thought. Classified information, something he didn't need to know. Well, he was used to that. He gestured for the guard to accompany him to the doorway, therefore, where they joined the other guards on the lookout for threats to the King.

“Summon a platoon of men,” the King then said to Amberley. “No, make that two platoons. This building must be guarded. There may still be Carrow soldiers roaming around. Make sure mister Shanks is kept safe while he does his important work.” The Field Marshall nodded and gave orders to the soldiers around him. “In the meantime, I'm going back to the Tower. The Queen is no doubt waiting with growing impatience for an explanation for everything that's been happening.” He left the room, heading back to the carriages, and Balhern and Darnell fell in behind them, along with his men.

Finding himself once again alone in the room, Shanks took another long look at the alternator, still humming and buzzing busily to itself as it emitted the mysterious emanations that were so agonising to the Radiants. Then he headed into the storeroom to find what he needed to build more of the machines.