This time around, the East Side Kids, a gang of well-meaning young rough-necks in New York, are pulled into a murder mystery.

They manage to rescue a young girl by the name of Sylvia from her violent stepfather Morley's abuse.

Soon after, the stepfather is killed by a gangster called McGaffey for interfering with his racketeering operation by stealing his money.

Rusty discovers that the grandfather blinks morse code, and interprets it, revealing that McGaffey is the killer.

They decide to go to the warehouse, and Rusty takes Sylvia to the police station to tell them who the killer is and to get Danny out of jail.