Ralph Montgomery, a successful real estate agent, is married to his younger wife, Ethel. He pampers her by hiring a cook, Mrs. Sutton. Ethel drinks only coffee and Ralph only hot chocolate, which is about their only point of difference. Ethel is also active in the drama club with a handsome young leading man as her costar. Among Ralph's friends, the current topic of discussion is the whereabouts of a Mrs. Andrews, a cook who has murdered three of her lady employers with arsenic poisoning. At Ralph’s office, he suffers an attack of indigestion or so he thinks, and goes home. In his workshop, however, he finds a can of arsenic, and coupled with the fact he knows very little of Mrs. Sutton, an employee of only a month, he becomes suspicious.