"Minnie the Moocher" is most famous for its nonsensical ad libbed ("scat") lyrics (for example, "Hi De Hi De Hi De Hi").
A spectral walrus — whose gyrations were rotoscoped from footage of Calloway dancing — appears to them, and begins to sing "Minnie the Moocher", with many fellow ghosts following along, during which they do scary things like place ghosts on electric chairs who still survive after the shock, and a cat feeding her kittens so much milk that they grow big immediately while the mother become so thin and dies.
After singing the whole number, the ghosts chase Betty and Bimbo all the way back to Betty's home.
While Betty is hiding under the covers of her bedsheets, her runaway note is torn up and the remaining letters read "Home Sweet Home".
In 1933 another Betty Boop/Cab Calloway cartoon with "Minnie the Moocher" was The Old Man of the Mountain.
Some of these songs indicate that Minnie's boyfriend Smoky was named Smoky Joe as well.