Arsenic and Old Lace by Joseph Kesselring

Mortimer Brewster is a drama critic who must deal with his crazy, murderous family. His family includes two spinster aunts, Abby and Martha Brewster, who have taken to murdering lonely old men by poisoning them with a glass of home-made elderberry wine laced with arsenic, strychnine, and "just a pinch" of cyanide. Mix this with the return of Mortimer’s murderous brother, Jonathan, who has received plastic surgery performed by Dr. Einstein to conceal his identity, and now looks like horror film actor Boris Karloff. Mortimer starts debating whether to go through with his recent promise to marry the woman he loves, Elaine Harper. Can he really subject her to this murderous family? Find out in Arsenic and Old Lace!