When the murder of an archaeologist puts a valuable medallion into their hands, Abbott and Costello waste little time in trying to sell it, only to find themselves pursued by police, a slinky adventuress, an Egyptian high priest, and the mummy himself.

Flash Fulton (Bud Abbott) and Weejie McCoy (Lou Costello) take pictures of a bank robbery. Lured to the mountain resort hideout of the robbers and accompanied by Dr. Bill Elliott (Patric Knowles) and Peggy Osborn (Elyse Knox), they also meet old friend Johnny Long (Johnny Long) and his band and singer Marcia Manning (Ginny Simms). Dr. Elliott and Peggy are being held in a remote cabin by the robbers, but Weejie rescues them by turning himself into a human snowball that becomes an avalanche that engulfs the crooks.

Abbott & Costello are two bumbling (naturally) American cops, on exchange in London, hunting for Mr. Hyde, the monster that has been terrorizing the city.

Two hapless waiters in a tavern on the Spanish Main play cupid between aristocratic Lady Jane and tavern co-worker Bruce Martindale, but the two bumpkins mix-up a love letter with Captain Kidd's treasure map of Skull Island, leading to them being kidnapped and taken off to the notorious pirate's island.

Harry and Willie are scammed into buying the Thomas Edison studio lot by a man named Gorman. They decide to follow Gorman's trail to Hollywood where, unbeknownst to them, he has taken the identity of a foreign film director. The lads wind up as stunt doubles in film the which Gorman is now shooting, while the conman tries to have the bungling pair done away with before they realize who he really is.

Lester and Orville accidentally launch a rocket which is supposed to fly to Mars. Instead it goes to New Orleans for Mardi Gras. They are then forced by bank robber Mugsy and his pal Harry to fly to Venus where they find a civilization made up entirely of women, men having been banished.