Deepstar Six (1988, dir. Sean S. Cunningham)

An undersea naval facility disturbs a monstrous sea creature. Slightly tatty Alien clone trying to steal The Abyss‘s thunder at the late 80s box office. A cast of TV faces and some fun-though-budget model and creature effects help pass the time. One great jumpscare, mind you, and some interesting character details in passing.

Leviathan (1989, dir. George Pan Cosmatos)

A deep-sea mining team encounters a sunken Soviet ship harbouring a mutant organism. Cheesy Alien/The Thing hybrid/ripoff, made to piggyback the release of The Abyss. Perfunctory direction and script, but a couple of neat Stan Winston-designed monster moments and a fine cast of character actors offer some entertainment.