The family had deliberately misdirected Poirot, as they each know Gerda is the murderer, and are attempting to save her from imprisonment. Gerda had taken two pistols – shooting John with one, and then planning to be discovered with the other pistol in her hand, later proven not to be the murder weapon. Immediately, Henrietta understood that John's final appeal was for her to help Gerda. Instinctively, Henrietta assumed the responsibility by dropping the gun into the pool, and later goes back to retrieve the second weapon. She hides it in a clay sculpture of a horse in her workshop to avoid the police searches. Later, she gets it handled by a blind match-seller and then places it in Poirot's hedge.