Terry-Thomas was the original choice for the role of Dr. Ezra Mungo.
A poster for this film is featured in From Russia with Love. It shows an Anita Ekberg head shot on the side of a building when 007 and Ali Kerim Bey are about to assassinate Krilencu. A window opens (appearing to be Ekberg's mouth) and Krilencu exits the building on a rope and is shot. After the assassination, 007 makes one of his inimitable quips as he says: "She should have kept her mouth shut". Both films were from United Artists. Note, however, that the relevant chapter of the Ian Fleming novel was titled "The Mouth of Marilyn Monroe".
Many of the key technical personal from the early James Bond films had the same jobs on this film. Ted Moore was the DP, Syd Cain was the art director, Maurice Binder designed the titles, John Stears did the visual effects, Monty Normal composed the music, Johanna Harwood was a scriptwriter.
This is, to date, the only film produced by Eon Productions that is not part of the James Bond franchise.