While it has some other, smaller assets, The Duke Is Tops is worth seeing primarily to witness Lena Horne's screen debut. Looking as if she were just barely old enough to be out alone at night, Horne lights up the screen in her several musical numbers. In her dialogue sequences, Horne comes across as slightly tentative; she hasn't really learned how to play a scene yet, and some of the emotions come across forced. But she still has that special sparkle, and when she favors the camera with a song, she fills the screen with life and energy. (Her rendition of "I Know You Remember" is especially noteworthy.) In the male lead, Ralph Cooper is also a bit stiff, but he does have a certain charisma, and a number of the specialty acts -- such as Rubberneck Holmes and the Cats and the Fiddle -- are well worth experiencing. The plot and screenplay are fairly poor, although they do provide for a memorable medicine show sequence. Production values are on the skimpy side, and the whole look of the film is fairly chintzy, but as long as Horne and her cohorts are warbling and grooving, most viewers won't mind.