Underwater
Take the first two Alien movies, put them underwater, replace Sigourney Weaver with Eminem during his angsty 15 year old girl phase, make the acting much, much worse, throw up on it a bit, then you have Underwater.
This is about as formulaic as you can get for a movie. Highly predictable, provides no setup at all. Honestly it felt like the first half of the movie was cut out. And it's just really bloody boring.
And to make things worse, the ending hints that it's setting up for a prequel or setting up its own Universe (King Kong style), but in the end it's just a crap movie that's not worth the watch
2/10
(1 point for the cool looking Chthulu)
PS; if I ever have to see Kristen Stewart in her underwear again, I'm removing my eyes