The Abyss (1989) on Netflix

When an American nuclear submarine crashes, the United States Government believe the Russians to be responsible. They enlist the help of a team of underwater drilling platform workers who are to help the deployed Navy SEALS locate the crash site. As they get closer to their destination, the friction between the two teams increases. When some workers report seeing UFO's underwater, the SEALS grow increasingly suspicious and suspect a Russian mini-sub. After a series of near-fatal disasters, the workers find that they are the only people who are capable of stopping World War III. But they are not the only inhabitants of the deep, and strange things are happening back at the surface...