Loosely based on the mysterious death of Serge Rubinstein, a Russian-born financial wizard and stock manipulator who was found murdered in his New York apartment in 1955. The murder remains unsolved.
This film and The Falcon's Brother (1942) are the only two films to feature Tom Conway and real life brother George Sanders. They played brothers in both films.
George Sanders (Clementi Sabourin) was the ex-husband of Zsa Zsa Gabor (Mrs. Ryan). They were married from 1949 to 1954. He was later married to her elder sister Magda Gabor from 1970 to 1971.
George Brent was to have starred in the film, but took ill after a large party scene with many, many extras had been filmed. Rather than an expensive re-shoot, the producers left the scene (with him visible) in the final cut. He was replaced in the lead by George Sanders.
The airplane shown bringing Clementi's mother from Europe is a SAS (Scandanavian Airlines System) Douglas DC-6B, registration SE-BDT. Built in 1953 it flew with SAS until 1960, when it was leased by Thai Airways until 1964 when it was scrapped.
The sign outside a church that Clementi sees at the end of the film is a verse from the Bible - Mark 8:36.