"Arsenic and Old Lace" is a dark comedy play written by Joseph Kesselring, first performed in 1941. The story revolves around two elderly sisters, Abby and Martha Brewster, who run a boarding house in Brooklyn. They are known for their charitable nature, but they have a sinister secret: they poison lonely old men to help them find peace. The plot thickens when their nephew, Mortimer Brewster, discovers their actions while dealing with his own family issues, including another nephew who believes he is Theodore Roosevelt. The play explores themes of family, sanity, and the fine line between kindness and madness.