Birdie Tomlinson, sister to Louis Tomlinson had just turned twenty-one.
Her brother and his band mates have reunited in New York for few weeks to work on a new single.
Louis has planned a party in honor of his sister and invited his friends and hers.
While drinking and partying the night away, Birdie and Harry hit it off.
After a drunken mistake and a one night stand, Birdie and Harry hide their secret from Louis.
But with all of the time that the band and Birdie spend together only bring her and Harry closer.
Will Harry and Birdie continue their romance or will family and friends drive them apart?