The mice are on the loose after hours in a doctor's office, playing with the various pieces of medical apparatus. Susie Mouse is caged for research until her lover Johnnie frees her. A mouse orchestra plays a swinging wedding song. But throughout, a cat is stalking...
| Actor | Role |
|---|---|
| MMargaret Hill-TalbotMouse | Mouse |
 Mel BlancCat (voice) (uncredited) | Cat (voice) (uncredited) |
 Bernice HansenJohnny Mouse / Susie Mouse / Various Mice (voice) (uncredited) | Johnny Mouse / Susie Mouse / Various Mice (voice) (uncredited) |