The pièce de résistance in Diamonds Are Forever, in which CIA helicopters raid the oil-rig command post of Blofeld (Charles Gray) in Baja California. Aboard the rig, Blofeld commands an orbiting laser satellite, powered by a huge diamond solar shield, that can wipe out any target on Earth.
As Blofeld waits for the Western powers to provide a huge ransom—otherwise Washington, DC, will be destroyed—Bond (Sean Connery) arrives inside a giant inflatable ball that has been dropped into the ocean near the oil rig. His mission is to somehow enter Blofeld’s control room and substitute a phony command cassette for the one being used to guide the satellite. Why would Blofeld allow him anywhere near the navigation apparatus for the satellite? Because Bond villains notoriously reveal their plans to 007 before they kill him. It’s an unspoken rule.
Bond achieves his mission—but, unfortunately, Tiffany Case (Jill St. John) misinterprets his subterfuge and actually switches back in the real cassette. By then, the CIA helicopters have launched their attack on the oil rig, which Blofeld defends using antiaircraft cannons, machine guns, and armor plating. The sudden attack—initiated by Bond, who thought the cassette swap was successful—actually confuses Blofeld and his missile expert Professor Dr. Metz (Joseph Furst). Thanks to some direct hits, the command center is blown apart, and the satellite’s laser cannon is neutralized.
Bond, meanwhile, has found Blofeld trying to escape in his bathosub. Knocking out a crane operator, Bond assumes control of the winching mechanism and begins to have some torturous fun with the SPECTRE chief. Lifting the sub out of the water, he eventually slams it into the control room, supposedly killing Blofeld—although he returns briefly in a wheelchair in the pre-credits teaser of For Your Eyes Only, and is later resurrected for the Daniel Craig films.
The oil-rig battle was filmed aboard a studio-customized oil rig that was rented and placed off the coast of southern California, near Oceanside. The rig itself was a portable, floatable device built around a barge-like structure with enormous retractable sea legs. During filming, the crew was based in Oceanside at the Bridge Motel. Each morning, helicopters would transport the cast, director, and immediate production staff to the rig, while boats carried the extras and technical crew.
At a nearby dirt airfield, other choppers were being prepared to serve as the CIA attack force for their assault on the rig. Each one was outfitted with special effects weaponry, including metal tubes filled with electrically activated powder charges that simulated the whoosh of air-to-ground rockets, and small strobe lights that simulated the fire of machine guns. During one sequence that doesn’t appear in the finished film, the helicopters dropped demolition-carrying frogmen into the water around the rig to prepare for the rig’s final destruction. According to writer/director Robert Short, who observed some of the oil-rig sequence in 1971, the deleted sequence explains the presence of frogmen on the film’s final release poster.