
Wealthy Lily Parkhurst has been living on borrowed time for years thanks to a bad heart. Her greedy cousin and companion Harold rushes her overdue demise with a well-planned poisoning, knowing there will be no autopsy. Harold hadn't planned on the old lady's cockatoo, Radcliffe, being such a blabbermouth about what he's witnessed.
Arthur Randall's marriage has become a sham (and he is in love with his secretary), but his wife doesn't wish to give him a divorce. It is suggested to him that he and his wife go away for a while in an attempt to work things out. She reluctantly agrees, and they go to their cabin by the lake. While they are boating, Arthur's wife falls overboard and drowns. Before she drowns Arthur pulls a ring from her finger- a ring he intends to give to his secretary. Arthur returns home for a while, but is eventually drawn to return to the scene of his crime.
A wealthy woman who's raised a nephew in luxury has tolerated the insolent young man long enough. She informs the ingrate that she's changing her will to remove him as sole heir to her estate. Before she can act, he intends to exploit her heart condition and pin the murder on "the monster", a crazed killer roaming the countryside. Richard doesn't realize that the aunt is already anticipating his scheme.