Diary of the Dead

Stan (Hector Elizondo) and Vera (Salome Jens), a childless couple, live with Vera's mother, Maud Kennaway (Geraldine Fitzgerald) Maud dislikes and is openly contemptuous of her infertile son-in-law. Stan dumps Kennaway's nitroglycerine pills down the toilet and replace them with worthless sugar substitutes. Maud wakes up, finds the body, and accuses Stan of murder. Stan manages to dodge all her blows with her cane, which causes her to stumble and cut her head.