Herbert Lom (Chief Inspector Dreyfus of the Pink Panther movies) as a man suspected in the murder of his wife and her lover (their bodies had been found at the beginning of this show) -- but in this scene it's revealed that the wife's lookalike daughter did it herself in a fit of insanity and buried the memory -- only to regain it when McGarrett recreates the night. The daughter seems to have an 8-shot revolver, which is fairly rare. This show revolves around a portrait of the murdered lady, and is reminiscent of a mystery-suspense film called "Laura" which is one of the favorites of film noir devotees.
Great idea McGarrett to have a conversation with a crazy distraught women who has already shot you once and now has a gun to your head at much closer distance.