A young Irish guitarist and a sheltered young cellist have a chance encounter one night above New York's Washington Square. They are soon torn apart, leaving in their wake an infant, August Rush, orphaned by circumstance. Now performing on the streets of New York City and cared for by a mysterious stranger, August uses his remarkable musical talent to seek the parents from whom he was separated at birth.

Nick knows exactly how long it has been since Tris broke up with him - three weeks, two days, and 23 hours. Now she is at his gig, with a new guy. Nick can't understand how she could have moved on so fast. But that night, Nick meets Norah. They have nothing in common except their taste in music. This begins the night of Nick, Norah and Manhattan. Now, this chance meeting will turn into a crusdade to find a legendary rock band's secret show, ends up...