The New York Museum of Science and History had itself a curious mystery! Somehow, each night, an exhibit was broken, and it went on too long to be a practical joke. That's the setup that led Mona Lisa and Raphael to investigate, and inadvertently free, the ancient mutant inventor Ptah from his centuries-long imprisonment. Now, teamed up with the friendly mutant mummy Bakari, our heroes must stop Ptah from conquering the city. Plus, Shredder tries to escape an imprisonment of his own!