sentences:  The experience led Fuller to add film sequences where Francen gets his fingers caught in a hatch, using a submarine's red lighting to enhance a love scene, and having a battle between two submarines staged much like a hunter stalking his prey.When cinematographer Joseph MacDonald said there was no room on the sets for the red lighting, Fuller said that few in the audience would be familiar with the equipment inside a submarine and therefore had MacDonald place them in the audience's view.The U.S. government, who provided the nuclear bomb explosion footage that opens the film, insisted that certain spectrum colors be eliminated from the sequence, lest it "could reveal nuclear secrets".