Jerry and his babysitter, Alice, meet two androids named Fi and Fum. Fi and Fum talk Jerry and Alice into going for a ride in their flying saucer, but when attempting to return them home, they find themselves in a place in time where everyone has numbers for names.

The saucer lands at a time when all inhabitants on the planet are shrunken down to save resources. Jerry, Alice, Fi and Fum meet these tiny folks, and they discover they distrust anyone larger than them.

Our heroes land in a time of simpler robots. Fi and Fum decide to give lessons in proper robot behavior to an outcast robot in need of help.

In Transylvania, our crew is met by a descendant of Dr. Frankenstein, who is also up to no good. Before Jerry and Alice know what's happening, he reprograms Fi and Fum, turning them into his personal minion droids.

When the lost saucer crashes into the underwater city of Atlantis, its ruler, Nepto, converts the saucer into an underwater TV station and forces Fi and Fum to perform on cameras.

The crew of the Lost Saucer arrives in a strange land. Everyone there is invisible. "The crew of the Lost Saucer arrives in a strange land where everyone is invisible."