Three characters from the original Michigan Chillers series come together in The Michigan Mega-Monsters. Rick Owens, Leah Warner, and Sandra Johnson are staying at a camp in Rochester Hills, Michigan. After hearing a legend told by a counselor, they go exploring into the forest searching for the Mega-Monsters to see if they exist.
The three kids find a castle which turns out to be run by the Camp Director. He explains that the Mega-Monsters were created from a horrible accident that mutated tadpoles. With the children's help, Mr. Williams returned the tadpoles to normal.