I was watching old Disney cartoons on DVD, and found this one called Runaway Brain. Watched it 3 times in a row. It's about Mickey trying to get $999.99 by becoming the subject of a scary experiment - mind transplant with a... um... (thinks how to word it nicely) maniac. This is the maniac in the body of Mickey.
...
Ooooooor it could be
normal Mickey when he sees Minnie in a skimpy bikini
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