Chief Petty Officer Gleason
Chief Petty Officer (CPO) Gleason served as the crew chief aboard the Seaview. He had a strained working relationship with his subordinate, Seaman Smith. Nonetheless when the Seaview became stuck in a minefield, Gleason cooperated with Smith to free the ship by going out in a minisub to cut the mine cables. An accident wherein the severed mine exploded flung the minisub against another mine, killing both Gleason and Smith.
- Theodore Sturgeon's novelization of the film has Gleason and Smith die differently. After they succeed in freeing the Seaview, a UN sub attacks. Gleason pilots the minisub into the path of a torpedo, which destroys him and Smith and buys the Seaview time to escape.