The Abyss

When a nuclear submarine sinks, a team of divers descends the depths to conduct a rescue mission and to determine the cause. Led by "Bud" Brigman (Ed Harris), the crew includes his estranged wife (Mary Elizabeth Mastrantonio), who's an engineer, and a paranoid Navy lieutenant (Michael Biehn) with an agenda. During the investigation, it becomes evident that an extraterrestrial power is at work. The film reeled in an Oscar for Best Visual Effects.