Uncut (2009)

Seven people and their desperate search for escape, only one will survive. The last performance of a pantomime is held at an old, isolated theater in provincial England. The show has been a disaster, attracting only a handful of locals. The final party afterwards turns out even worse and some of the cast and crew slip away for their own private session in the creepy basement. Amongst the group are the enviable pantomime leads and real-life lovers Clarice and Nathan, currently not speaking, the womanizing director Derrick and the thirty-something, obscure stage assistant Janet. As their bash kicks off Derrick disappears, only to be found with his throat savagely slashed. When they discover that they're locked in the next victim dies. The killing continues. Paranoia grows. Nobody can be trusted.