By 1942, with the release of "Who Done It?" Universal Studios had learned a thing or two about Abbott and Costello: Namely, that the ridiculous boy-girl subplots and the subpar music (except from the Andrews Sisters) that padded their other features to date where wholly unnecessary. Thankfully, Bud and Lou are given full reign in "Who Done It?" without any extraneous material.
That said, it's easy to see who "Who Done It?" is my favorite of all their features. Not only are "the boys" in top form, but the supporting cast is great as well; Mary Wickes is a perfect foil for Lou (bringing to mind his earlier clowning with Joan Davis in "Hold That Ghost"), and it's a shame the two didn't work together more (even *her* talents couldn't pump any life into "Dance With Me, Henry").
Abbott and Costello comedies are often long on laughs but short on plot. Not the case with "Who Done It?" The ins and outs of a radio spy ring are well crafted, providing appropriate counterpoint to the antics of Bud and Lou.
And what antics there are! Lou is convulsively funny here, from the opening moments where he deals with an obnoxious elevator boy (and "wins" a bet concerning the production of orange juice) to the later chase on the studio rooftop (and clever use of the sign "Vote for Townsend Phelps"). Classic bits--such as the insanity of "Alexander 2222", which reaches a new and self-deprecating conclusion--are here as well.
Sadly, Universal didn't remain knowledgeable about what to do with A&C for long; soon after, the love stories and drippy songs were back. But "Who Done It?" remains as a testimony to what this incomparable comedy team could achieve on its own.