20 Things You Didn’t Know About For Your Eyes Only (1981)
7. “Conserve Your Oxygen.”
The submerged Greek temple that Melina Havelock is preserving in honour of her parents was constructed underwater in The Bahamas, which also played host to the submerged shots of the wince-inducing keel-hauling sequence.
However, Carole Bouquet’s underwater scenes were filmed on a dry soundstage at Pinewood Studios because the French actress had sinus problems that prevented her from diving or remaining submerged for the periods of time required to capture the underwater close-ups.
Whilst lighting effects, wind machines, and slow-motion editing were used to create the illusion that she and Roger Moore were underwater, the bubbles produced by their breathing were added optically in post-production using Alka-Seltzer overlaid above the studio-shot footage.