Ward's car is a 1937 Lagonda L6 45R Rapide. Only 25 were made. Fully restored, at auction in 2016, one could easily sell for in the high six-figures.
Kim's car is a 1956 Bentley S1 Continental drop-head coupe. Only 431 were made from 1955-59. As of 2016, such a car, fully restored at auction, could easily fetch over $500,000.
The hair raising car racing sequence was not simulated,
and performed by the two leads Richard Todd and Anne Baxter
without stunt doubles. It took several weeks to shoot.
After the closing credits and Douglas Fairbanks Jr. is listed as one of the two producers, Fairbanks appears and asks the audience to keep the ending of the movie a secret.
In an article in the October 29, 1956 edition of the Los Angeles Times, David Niven was announced as the male lead for this film.