SeaQuest DSV

In the early 21st century, mankind has colonized the oceans. The United Earth Oceans Organization enlists Captain Nathan Bridger and the submarine seaQuest DSV to keep the peace and explore the last frontier on Earth.

Lostland (Season 2, Episode 12)
The Seaquest finds an ancient helmet which seems to be from the lost city of Atlantis. A professor arrives to debunk this theory. However, the helmet starts warping the minds of the captain and some of his men.

Brainlock (Season 3, Episode 11)
On the eve of the signing of the new UEO charter, President Alexander Bourne and Larry Deon conspire to gain control of Lieutenant Fredericks' psyche-implant in order to program her to assassinate Secretary General McGath and cripple the UEO beyond repair.