Gone (2012) http://www.imdb.com/title/tt1838544/
A year ago Jill was abducted from her home and dropped in a deep hole in the woods. She escaped and reported the incident to the police. As the cops couldn't find the hole she was talking about, nor could they find any evidence of a break-in at her house, they chalked it up to her imagination. She continued to press the police for action until they had her involuntarily committed for psychological study. She was eventually released under psychiatric care.
Eventually her ex-alcoholic sister moved in with her. After an all-night shift working at the diner Jill returns home to discover her sister is missing. Again - no evidence of any break-in at the house, but the sister is missing. Jill tells the cops, they don't believe her. Convinced that the dude Jill escaped from over a year ago is behind her sister's disappearance she gets a gun and tries to track him down herself while avoiding the cops trying to rein her in.
Stars big-eyed Amanda Seyfried as Jill. Jennifer Carpenter (from Dexter) makes an appearance as Jill's coworker, but her presence is sort of wasted. Ah well, a girl's gotta eat. Some other folks you may or may not recognize are in the film too.
As a thriller the film doesn't do too bad. It is entertaining and engaging through to the end. I thought the script and acting did a good job of keeping the audience wondering if there really is a kidnapper or is Jill bonkers and making shit up. Especially 'cause Jill sure can straight-faced lie to folks. Heck she lies to practically everyone she encounters, which just makes the viewer wonder all the more what's real and what isn't. Sure, there are a couple scenes that are a little off, but nothing terribly damning of the film.
Nutshell: not a bad choice for a thriller flick. Not a great groundbreaking film neither, but a relief in that it certainly could have been worse and wasn't.