Slip and the gang stray from newspaper work to detective work.

An electric shock enables Sach to predict numbers, so the Bowery Boys are off to Las Vegas to win enough money at the roulette wheels to let their landlady buy an apartment building. Witnessing his winning streak, some gangsters decide to move in and find out his "system" for beating the odds.

When a cold medicine causes Sach to be able to smell diamonds, he and the rest of the Bowery Boys are induced by a diamond dealer to accompany him to Darkest Africa in search of a legendary cache of them.

Rejected by the Army, Marines, and Navy for being too young, the punks help the war effort by throwing fruit at a shop they believe is owned by a Japanese American. Confronted by him wielding a short sword, the gang decides to come back at night but find him dead.

A chorus girl's career is ruined and her brother is driven to suicide when she starts smoking marijuana.

Slip, Sach and the rest of the Bowery Boys enter a haunted house, where they engage in slapstick with a gorilla, a robot and a vampire

The Bowery Boys--Slip, Sach, Bobby, Whitey & Chuck--start their own exterminating service, and get a job which takes them to a spooky old abandoned mansion in the middle of the night. Meeting up with pal Gabe and his new French bride, the boys are tormented by mad scientists who try to convince them the place is haunted and then kidnap Sach in order to place his brain inside a gorilla.