We tracked Kaden Novick on my tabphone, and Alex relayed his location to everyone who was out looking. Eager to talk to him about murder, I decided we'd join the chase.

"He's on the move," I said to Alex and my earpiece as we left the station, entering the artificial winter sunlight. "Coming south, towards us."

Alex drew ahead, saying the same thing to the PRBs he was in contact with. A handful of them were taking off from the station roof behind us, flying beneath the concrete sky.

"Stay on the line," I said into my earpiece. Then, to Alex, "There are some officers on patrol near the area. They're closer than anyone from the drugs squad, so they're joining the search. Let's go."

We burst onto the high street, sprinting towards a tram that had just stopped. A group of people were huddled in front of the doors, waiting to get on. Alex pushed through them with his warrant card held up and climbed aboard. "Police!"

I jumped on behind him. "This is a matter of urgency! Go!"

The doors slammed shut, and the tram screamed away. I caught a glimpse of the people who'd been waiting, all looking pissed off. This wouldn't have been a first for them: in times of emergency, police transport was the trams. Only paramedics and firefighters got independent vehicles. The streets were too narrow for anything more, and the risk of hitting people was too great.

I paced in the limited space near the doors, listening to the patrolling officers on my earpiece. It sounded like they'd spotted Kaden Novick but were struggling to keep up.

"Don't let him out of your sight!" I barked. "Alex, they're near Nova Drive, still heading south. I want us to come down the other way and block him in, so we need -- "

" -- the next stop," Alex finished, thankfully familiar with the city now.

A minute later, the tram stopped. We jumped off, and I led the way down a narrow street hemmed in by scruffy blocks of flats. My earpiece came to life again as we pounded the tarmac. "...lost...turned the corner..."

"No!" I said. "Damn it! Alex, get onto the PRBs again."

We turned the corner and almost slammed into two teenagers coming the other way.

"Give them our location," I gasped. "Have them come in from the east and west. We'll trap the bastard in this area one way or another."

Alex tapped his earpiece and gave his commands. I scanned the area around us, trying to look with the precision of a robot. My sight was clearer with adrenaline pumping through me: I saw the cracks in the brick walls and shapes in the shadows between the buildings. But no suspect.

"Caught up!" my earpiece squawked. "Turned... Diamond Lane..."

We flew around the corner.

Kaden Novick was tearing towards us, his hood pulled down over his face. Two uniformed police officers were running a long way behind him.

A metal staircase leading to the walkways stood between us. Kaden glanced at it.

"Police!" I yelled, drawing ahead of my sergeant.

Kaden slowed, his eyes widening. I launched myself at him in a tackle.

His boot flew up. I twisted away, and it hit my shin. He sidestepped. I landed on the road alone.

As I rolled over, I heard the smack of a fist meeting skin and a yell. There was a flash of black in the corner of my eye, and Kaden shot past, up the metal stairs that would take him to the higher walkways.

Alex staggered backwards and caught the railing. His jaw was bloodied, the skin split. He pushed himself away and strode towards me.

"All right?" I asked.

He gripped my arms, pulling me to my feet. "Yeah. You?"

"Yeah." I took off again.

Alex followed me up the stairs. The two patrol officers were closer now, and the steps rattled as they climbed behind us. The walkway went up and up, staggered by long landings with twists and turns that would lead us back towards the high street.

Alex drew alongside me, and I had to take the stairs two at a time to keep up. "We need to get -- "

But he was already on it, telling the PRBs our current location.

We reached the first landing and shot past a mother and toddler sitting on a bench tucked into the corner. They gawped as the walkway shook. More steps rose ahead, and we sprinted up them.

The second landing branched off in different directions, towards the doors of the businesses that were level with us or twisting away to create more paths. I could see Kaden up ahead in his hoodie, forking to the right down a narrower section I knew well. He turned a corner and vanished.

"Dead end!" I drew my weapon.

Alex shouted at the PRBs in his earpiece, and we barrelled around the corner.

Kaden was coming back the other way, having seen his mistake. He slowed when he saw us, lifting his fists.

I raised my pistol. "Don't move!"

Kaden ignored me, turning around to see if the stone wall behind him had been a figment of his imagination. Four PRBs landed on the other side of the walkway to block him in.

He sighed loudly and raised his hands in the air.

I holstered my gun and strode towards his back. "Kaden Novick, I am arresting you for drug dealing, drug possession, and assaulting police officers." I took his wrists and cuffed them together. "You do not have to say anything, but it may harm your defence if you do not mention, when questioned, something which you later rely on in court. Anything you do say may be given in evidence."

Two PRBs came forward and gripped Kaden by the biceps. I turned around to lead our way back to the station, my breaths finally starting to slow. My shin was throbbing.

Alex was leaning against the railings, holding his jaw. He straightened up as I approached and offered me a pained smile.

I fell into step with him. "Not bad, Sergeant."

***

Once Kaden had been put in an interview room with a PRB on guard, we waited for a solicitor to arrive at the station. Alex searched for an ice pack, and I studied Kaden's criminal record. He'd been arrested on drug charges before, but always possession, never dealing. He'd either been lucky or the dealing was a recent thing.

"But what's your connection to Zoe?" I murmured.

Zoe didn't come up anywhere on his national profile, and she wasn't linked to his Xplora account in any way. There was also no indication in her post-mortem report that she'd ever taken crimson.

At least Bryony's finances matched up with Jason's story.

I was just shutting everything down when Alex returned, holding an ice pack. He opened the office door and leaned against it. "Solicitor's turned up."

"That was fast." I stood. "I'll question Kaden alone. I don't want his ego to get any bigger, and you walking in there with a bruise the size of a melon is just going to make him smug. Look at Bryony Gold's tabphone, and check Zoe's again too. Make sure she wasn't in the habit of talking to Kaden Novick."

"Zoe?" Alex looked down at me as I stopped in front of the door. "She wasn't a user. Her post-mortem testifies to it."

"I know, but check anyway. I don't want to leave any stones unturned."

Alex sighed and squeezed past me. His arm brushed against mine, and my heart jumped. Something crackled in the air between us.

I bolted from the office.

***

After a discussion with the solicitor, I sat down in the same interview room I'd not long spoken to Jason Castle-Ackerman in. Kaden Novick and the solicitor were opposite me. Kaden was sulking with even more ferocity than Jason had, staring down at his bloodied hands.

I went through my standard legal explanation, and then I dived into my questioning. "Where were you on the evening of Monday 26th December, between eight and ten?"

Kaden looked at his solicitor. The man nodded. I'd talked him through my suspicions about Kaden's involvement with the murders, and I'd let him know that Kaden's threats towards Bryony did not look good. His first defence was against a looming murder charge.

"The train station," Kaden said.

"Doing what?"

"Waiting for my supplier from Rosek."

"Has this supplier got a name?"

"Rex. I don't know his last name."

"Okay. We'll check the CCTV for the Rosek platform."

"You'll see me there, promise. After that, I was dealing."

I'd leave questions revolving around that to the drugs squad. "Where were you this morning between four and half-past? That's a little while before you went to see Jason."

"Meeting Rex again."

"At Socrico Train Station?"

"Yeah. He gave me some more Crimson."

"Didn't he do that on Monday?"

"Business around here is good."

"I assume there weren't any eyewitnesses to your exchange who can alibi you?"

Kaden shrugged. "Rex."

The testimony of a fellow drug dealer was hardly going to stand up in court. I leaned back in my chair and scrutinised Kaden. "Did you know Zoe Ackerman?"

"Everyone knows her. She was in the news. She married her step-brother."

"But did you know her personally?"

Kaden shook his head. "The only person I deal with from that family is Jason."

"You also used to deal with Bryony Gold, his girlfriend. We know she was supposed to be meeting you, and we've looked at her financial accounts. She was saving like crazy. She owed you something, didn't she?"

"The bitch stole crimson off me." Kaden's lip curled. "I told her she'd have to pay up."

"What would you have done to her if she hadn't?"

"I wouldn't have killed her."

"What would you have done?"

He looked away. "Don't know."

"Did Rex come with you to deal?"

"No. He went to the train station."

"Are you sure? He wasn't waiting in the wings to help you attack Bryony?"

"No!" Kaden raised his head, his hands curling into fists. "Try chasing him like a pack of hounds and ask him."

***

Back in our office, I found Alex glaring at two hovering tabphones and holding the ice pack against his jaw. He looked up without moving his head. "There are no messages from Kaden or anyone who could be him on either tabphone."

"Can you..." I stopped in front of his desk and hesitated. "Are you all right?"

He moved the ice pack and allowed me to see the bloodied bruise. I winced. It wasn't pretty.

"I've got a few things to ask the PRBs," I said. "Or try asking, anyway. Why don't you stretch your legs and go to Coffee Glitch? Get a medicoffee. Kaden really went at you -- I hope he didn't break your jaw."

Alex managed a smile. "I think I'd know if he had. But coffee would be nice."

"If Dixon catches you, they were my orders."

Alex left the office, taking the ice pack with him. I followed so that I could attempt to issue some orders to the PRBs.

Once I'd managed to get them looking for men named Rex in Rosek with drug convictions, I checked Kaden's national profile again. There was no link to anyone called Rex. No link on his Xplora page, either.

When I tried to close the pages, my tabphone froze.

I glared at it. "I don't have time for this!"

It responded by suddenly shutting down.

"What?" I held the power button, hoping it would turn back on. It didn't. "What are you doing? Fucking hell -- "

The office door clicked open. Alex entered, balancing the ice pack and two coffees in his hands. He'd obviously drunk some of his medicoffee on the way because amusement had cleared his pained expression. There was no doubt he'd just heard me.

"That was quick." I straightened up and tried to adopt a calm demeanour.

He handed me a paper cup. "It was quiet in there for a few minutes. What's wrong with your tabphone?"

"I don't know. It froze and shut down. Stupid thing."

"I'll have a look. And I still need to look at your earpiece, remember."

"Oh, yeah." I touched it automatically. "Thanks. I'm going to see how the PRBs are getting on. We're trying to identify Kaden's supplier, just in case that has anything to do with anything." Although I wasn't hopeful.

The PRBs informed me that they'd got a name. Eventually, I managed to make them tell me what the name was. Rex Lukens. Lived in Rosek. Previous drug convictions.

I trotted back to the office in the hope that I could borrow Alex's tabphone to make a call, but my own was sitting on my desk again.

He looked up. "All fixed."

"Really? You're faster than the PRBs! What did you -- actually, don't answer that." I removed my earpiece and threw it across to him. "Work your magic on this."

Alex caught it. "Did you get the name of the supplier?"

"Yeah, Rex Lukens." I sat down behind my desk. "I'll video-call Nina and see if she can catch the bastard."

Although we rarely had the chance to talk in our own time, Nina picked up after just a few rings. She looked the same as ever: soft, brown eyes; smart office clothes; brunette hair plaited cutely and pulled over one shoulder, a school style that her girlfriend was always teasing her about. She smiled, showing off bronzed dimples. "Hi, Ambie."

"Hi." I smiled back, filled with warmth at the sight of her. It really had been too long. "How are you?"

"I'm good. I'm sorry we haven't had the chance to talk much." She stood up and closed her office door. Just like at our station, she was working in a small glass cube. "I suppose this is something work-related?"

"I was hoping you could do me a favour."

"Anything for you."

"We've got a Kaden Novick here, arrested for drug dealing. He could be linked with an investigation I'm leading. His supplier is Rex Lukens and he lives in Rosek. I was wondering if you could get hold of him."

"I'll do my best."

"Thanks. How are your cases going, by the way?"

"Probably better than yours. I haven't found any high-profile stiffs yet."

"You've seen it all over Xplora, then?"

"Yes, courtesy of Clyde." She pulled a face. "I might have time to call you tonight, so..."

"I'll tell you about it then," I promised.

"Okay. Well, I'd better sort this out for you." She bit her lip. "But I don't really want to end the call so soon. How's your new sergeant? Better or worse than me?"

"I can't say too much." I looked up and realised that Alex was watching me. "He's in the room right now."

"Can I meet him?"

Alex stood up and came around the back of my desk. He braced his hands on the surface and bent over so that Nina would be able to see him. "Hello."

"Wow. Hello."

I wasn't sure whether she was wowing at his good looks or his shiner, so I decided to go with the assumption that would bring about a safer conversation. "We're also charging Kaden for assaulting police officers."

"I'll be careful with his mate, then." Nina looked over her shoulder. "Oh, my governor's coming. Got to go. I'll call you when Lukens is in cuffs." She winked at me, and the screen turned black.

I stared at my tabphone for a long moment.

"She's nice," Alex said.

"Yeah." I sighed. "How's the earpiece?"

"Not fixable here." He held it out. "Remember to give it to me again before we leave today. I'll take it home and fix it there."

"You have tools at home? Colour me impressed. I can stop calling expensive repairmen every time something in my flat breaks." Grinning, I glanced at the time. Nine o'clock. A decent hour at last. "Finish your coffee. We need to check these alibis."