Bubble (2005)

Shot with real people rather than professional actors, Bubble is a study in passion and repression. The film is set in a West Virginian doll factory and focuses on three employees there and their rather simple existence. An undercurrent of jealousy begins to develop and a horrific crime is committed.

What is very commendable in this film is the nervous tension in the story and the unpredictability of the characters. 

Official Site | IMDB