A graduate student and martial-arts expert rents a room in a house owned by a single mother who lives there with her son. A local street gang is trying to recruit the son, but the new tenant tries to help the boy's mother keep him out of the gang. When they learn of this, they target both the mother and her new tenant.

Los Angeles teenager Ritchie Valens becomes an overnight rock 'n' roll success in 1958, thanks to a love ballad called "Donna" that he wrote for his girlfriend. But as his star rises, Valens has conflicts with his jealous brother, Bob, and becomes haunted by a recurring nightmare of a plane crash just as he begins his first national tour alongside Buddy Holly.