Revealing mistake: At the end of the movie when they reach the surface, you can see that the horizon is nothing but a big wall with the sky painted on it. You can see the water splashing up against the wall.

Deepstar Six (1989)
Ending / spoiler
Directed by: Sean S. Cunningham
Starring: Miguel Ferrer, Greg Evigan, Nancy Everhard, Taurean Blacque
The Deep Star explodes and two survivors escape in a submarine. However, when they get to the surface the monster suddenly erupts from the water and attacks them, but it is killed when the male survivor blows up the submarine. The two escape to shore in a lifeboat.
BoreWorm




