Kristen Stewart goes into badass movie star mode in Underwater, a long delayed and surprisingly decent deep-sea horror/thriller from director William Eubank. While it stands to be the second big-budget box office disaster in a row for Stewart after Charlie’s Angels, it deserves a better fate. The movie is actually pretty good. The film doesn’t try to reinvent the wheel or work any miracles. It’s successful in a very basic way in that it engages from beginning to end, with an occasional effective scare, a constant sense of dread and high-pressure tension. Stewart stars as Norah, an underwater engineer on a drilling rig in the middle of the Mariana Trench. We first see her brushing her teeth as the lights around her flicker, accompanied by some dull thuds. She glances around, plays a little with a spider in the sink, and she isn’t too concerned. Then, “boom!,” her section of the rig implodes, blasting water all around her as she and another crew member narrowly escape to a temporary safe place. And by temporary, I mean safe for the next 30 seconds or so. Norah eventually finds herself squaring off against sea creatures on the ocean floor in a deep sea horror flick that’s decent enough to warrant a viewing, but far from classic. Stewart’s star power, and some decent effects, put this one over-the-top.