as Jonathan: Replaced Boris Karloff, who was not released from his stage contract for the film.
The film features a mix of Hollywood stars and original Broadway cast members: Arsenic and Old Lace (1944)
as Dr. Einstein: Jonathan’s nervous, enabling companion. as Jonathan: Replaced Boris Karloff, who was not
: Mortimer’s brother who believes he is Theodore Roosevelt and is busy "digging the Panama Canal" (burying the aunts' victims) in the cellar. as Jonathan: Replaced Boris Karloff