Bud and Lou are talentless aspiring writers who want to get jobs writing murder mysteries for the radio. In the meantime, they are working as soda jerks at the counter in the same building as the network. When a real murder takes place, Bud insists that they investigate, as he assumes that if they can crack the case they can have a leg-up on getting these jobs. Naturally, this makes the boys top targets for this killer. The movie turns out to have, not surprisingly, an angle involving the Nazis and spies--common sorts of propaganda additions for wartime films.

What is surprising, though, is Walter Tetley. He plays a role much like Bud did in IN THE NAVY, as some of the familiar Abbott and Costello routines (such as when they made change) are used with him as the straight man to Lou's idiot. Also, and this really surprised me, Tetley looked about 16 in the film but was a decade older. Apparently seeming younger than his real age was a natural for him in films, as he played the voice of Sherman in the "Mr. Peabody and Sherman" cartoons when he was in his mid-40s.

As for highlights and lowlights of the film go, there were a few low points. The scene where Lou runs away--through the doors and wall is priceless and really made me laugh. Also funny but completely stupid was the acrobatic sequence. This was supposed to be at a radio station and I kept asking myself "how are the people listening to the radio supposed to enjoy this?!". Otherwise, a very good film and it has a lot going for it--Abbott and Costello are still young and agile, there is no singing and the distracting love interest that Universal insisted on sticking in the early films is toned down--way down. As a result, this film doesn't suffer from all the distractions that are in their early films--no sharing the limelight and no silly (and pointless) production numbers. Instead, the focus is almost exclusively on the team--as it should be in a comedy. Because of all this, it's their best early film. It's funny, as it really is an early film (as it came in their third year in Hollywood) but by this film, the team had already made eight other films--churning out four a year in 1941 and 1942!

Who Done It finds our intrepid duo as soda jerks who want to be mystery writers and work on the Murder at Midnight Show. Bud and Lou go to a broadcast just in time to witness the real murder of the head of the network, Thomas Gomez.

So what do our two geniuses think to do? They decide to impersonate police officers and try and capture the criminal themselves. Interfering with a police investigation is an offense unto itself, but when Abbott and Costello do it, it's strictly for laughs.

The two cops who don't think it's that funny are William Gargan and William Bendix. Supposedly Costello was not happy with Bendix playing the dim bulb detective because he was getting more laughs than him. Mary Wickes who plays the secretary of Thomas Gomez also said she did not get along with Costello on the set.

The actual murderer turns out to be a very peripheral character who only had a couple of inconsequential lines before he's unmasked at the end. I tend to think there was probably more of his part, but it was edited out. Not that there are not a host of suspects like Patric Knowles, Jerome Cowan, Don Porter, Ludwig Stossel, and even Wickes and Louise Allbritton.

One actor who did not get any billing, but should have because he was very funny constantly getting the better of poor Costello was Walter Tetley who played the fresh mouthed young elevator operator. What he did to Costello bordered on sadism.

Who Done It is a fine slapstick burlesque of all these mystery films that all the studios were putting out back then. I guess it said that if even Abbott and Costello can solve a case anyone can.

Two soda jerks desperate to break into radio to have their murder mysteries produced end up investigating the real deal in this amusing slapstick comedy that is one of Abbott and Costello's funniest. Filled with gag after gag and some great comedy performances, this jump into slapstick from the start and never lets go. Lou's getting hoodwinked by a juvenile telegram boy, first losing five cents and a bunch of glasses of orange juice, and later tickets to a radio show he believed were for a previous performance, as well as falling for the old two dimes for a nickel gag.

More comedy is provided by a young Mary Wickes as the radio station secretary, and there are also amusing gags involving various takes on the old "Who on First?", including one where Lou wins a radio, turns it on and hears the real Abbott and Costello doing the routine, and being turned off by having to hear this again over and over again. Unlike other Abbott and Costello movies, this one doesn't have any musical numbers, but it focuses more on plot for a change and that makes it a bit better than some of the musical comedies they had done up to that time.