The address that Edwina gives when she calls the police was Ginger Rogers' real-life address: 1605 N Gilcrest.
The exterior shots of the Oxly Chemical Co. office building where Barnaby works were actually shots of the Executive Building on the 20th Century Fox studio lot. The building is now known as the Old Executive Building.
Among the movie star photos Marilyn Monroe taped to her bedroom wall when she was a foster child were several of Cary Grant. She was thrilled to be co-starring with him in this film, a break-through role in her then fast-rising movie career.
The sports car used in the film was a red 1952 MG TD Roadster, which was put into storage by 20th Century-Fox after filming wrapped. It was purchased by Debbie Reynolds in a 1971 sale of Marilyn Monroe memorabilia (despite the fact Monroe herself never owned the car). It sustained a dent in the front bumper when Cary Grant hit a fence while driving it. Reynolds had the transmission rebuilt, then put it up for auction in 2011. It sold for $210,000.