Open Grave (2013)

A man woke up in a pit full of dead bodies lying between the wild. He completely lost his memory and was trying to determine he was alive or a murderer. In that situation he ran away and broke into one house nearby and was controlled by one group of strangers with guns same to the others. They started conflicting each other because no one determined who was who. However, when they discovered one danger that threatened their lives, they were forced to team up before it was too late.