Starring Nancy Carroll, Frank Morgan, Paul Lukas and Gloria Stuart, The Kiss Before the Mirror is a riveting Pre-Code thriller from acclaimed director James Whale (Frankenstein). When Walter Bernsdorf (Lukas) kills his wife (Stuart) for having an affair, lawyer Paul Held (Morgan) takes on the case. Suggesting that Walter could be acquitted by means of temporary insanity, Paul not only realizes that this defense may work but that also some of the behavioral patterns Walter's wife showed in regard to her infidelity also are appearing in his own wife, Maria (Carroll). Paul realizes that if this defense could work once, it might work a second time.