A woman named Betsy Ann Smith from Wakefield, Virginia won a bit part in this film as a prize on The Price Is Right (1956).
Barbara Graham's response to the guard advising her to "take a deep breath, it's easier" was supposedly "how _the hell_ would you know". Apparently, it had to be cleaned up for the 1958 audience, which is ironic given the rather graphic nature of the scene.
The close-up of the fake label on sulfuric acid bottle identifies Gidding Chemical as manufacturer. Nelson Gidding was the screenwriter.
Director Robert Wise only came on board with the picture after Don Mankiewicz had finished the original script. Wise insisted the old screenplay be thrown out and a new one written. He later disagreed with the Writers' Guild decision to give Mankiewicz co-credit.
After the capture, there is a brief shot of the San Mateo County Jail. It's the real building on Sweeney Ridge, adjacent to what was then a Coast Guard Radio Station.