With a little extra effort, Columbia's Key Witness might have been a model B picture. John Beal plays inventor Milton Higby, whose treacherous ex-girlfriend is mysteriously murdered. As the number one suspect, Higby is in the doghouse witht he Law. Fortunately, it seems as though someone witnessed the crime; less fortunately, that someone has apparently disappeared from the face of the earth. Higby also tries to disappear by disguising himself as a bum, which only adds to his already mounting problems. So little critical attention was paid to Columbia's B product in the late 1940s that one reviewer labelled Key Witness costar Trudy Marshall as a "newcomer," even though she'd been in pictures since 1942 (Marshall, incidentally, is the mother of 1970s star Deborah Raffin).