Toward the end Mr. Wigwam watches the cleaning lady empty the waste basket while grimacing, implying to the viewer he's worried his scheme is ruined. However, the audience later learns this was all part of his secret plan. Wigwam's reaction was wrong for two reasons: the police might have noticed his consternation and decided to look in the trash themselves; and secondly, he would not act this way (since it was what he wanted in the first place) and his reaction was only to deceive the viewer, to help set up the twist in the ending.