Mice, seeking shelter from a storm, enter Dr. Jekyll's house. His cat chases them, ultimately crashing into the lab, where he mixes up some of the potion. He transforms, then rounds up the mice. Mighty Mouse comes to the rescue; in the fight, the lab catches fire. The mice escape, but the house rockets into the sky.
| Directing | Mannie Davis | Director |
| Production | Paul Terry | Producer |
| Writing | John Foster | Story |