Freed from his exile on Earth, the Doctor takes Jo on a test flight in the TARDIS, landing aboard SS Bernice, a cargo ship crossing the Indian Ocean in 1926. As events take a dangerous and unexpected twist, it seems that their fate lies in the hands of a traveling showman named Vorg and his assistant Shirna, who have just arrived on the distant planet of Inter Minor with an amazing intergalactic peepshow called the Miniscope.