After escaping Schmigadoon, SMG4 and SMG3 return to find answers, alongside Mario and unknowingly pursued by Mr. Puzzles. But after a mysterious fog engulfs the four of them, they find themselves trapped in a gritty musical city in the 1920's called Schmicago. Their only hopes of escape? Well, Mr. Puzzles and Mario need to find true love. SMG4 and SMG3 need to make a "happy end," whatever that is. But after a dead body turns up... things start to look to be a lot more difficult than they originally thought. Will they be able to make it out of this strange musical city before they too become victims of a mass murderer?