La Machine à explorer le temps

Yvette Mimieux was actually underage when shooting began (she turned 18 during the shoot) and was not legally supposed to work a full shooting schedule, but did. She was inexperienced, but as she worked on this film she kept getting better and better, so that by the end of the shoot the producers went back and re-shot some of her earliest scenes.

In the great hall whenever George is inside, parallel and perpendicular white lines are seen painted on the floor. The table arrangements do not conform to any arrangement that fits these lines. This is because the set was constructed over a studio parking lot and they did not put down a floor covering. The revealing parking lines are simply ignored. This info came from a special effects veteran who was on the set during the filming of these scenes.

Edited into Des agents très spéciaux: The Project Deephole Affair (1966)