Claude Chabrol made this film for an American company, Universal, and with some American and British actors in prominent roles. Each scene for the film was filmed in both French and English versions, with the result that it got widely released in Britain and America. The English-language version was mostly scripted by the veteran British film critic Derek Prouse. Chabrol, who spoke excellent English, was able to maintain complete artistic control over the project.
The script consisted of both English and French language translations on consecutive running pages.
Real world alcohol in the film:
Chivas Regal 12-Year-Old Blended Scotch Whisky appears throughout the film, first in the opening scene.
King George IV Gold Label Scotch Whisky appears.
Evelyn Wharton's party includes Haig Gold Label Original Blended Scotch Whisky, empty bottles of Haig's Dimple Pinch 15-year Blended Scotch Whisky (used as candle holders, one of which Paul wields as a potential weapon), Johnnie Walker Black Label Blended Scotch Whisky, and Highland Queen Scotch Whisky.
The English-language version of this film was widely exhibited in Britain in a double-bill with Michael Winner's "I'll Never Forget What's'isname".