A train speeds toward Bananya and Baby Sweet! It's all over! But just when all hope seems lost, the hero of justice, Bananya Man, appears! The duo find themselves entranced and decide to patrol the town, hoping to become heroes themselves. But then a menace from the skies threatens the peace...

Victim Banana lies on the floor in the kitchen of a train bound for parts unknown. Bananya and friends are gathered together by Police Bananya, who's investigating the incident. Someone among them must be the culprit... but the investigation comes to a standstill. Just then, they're joined by a great detective who can solve any case!