A charismatic young Irish guitarist (Jonathan Rhys Meyers) and a sheltered young cellist (Keri Russell) have a chance encounter one magical night above New York's Washington Square, but are soon torn apart, leaving in their wake an infant, orphaned by circumstance. Years later, performing on the streets of New York and cared for by a mysterious stranger (Robin Williams) who gives him the name August Rush, the child (Freddie Highmore) uses his remarkable musical talent to seek the parents from whom he was separated at birth.