It all begins with a text message. An anonymous message sent to the cell phones of a dozen young men and women. The message is an invitation to attend one killer of a party. Just who sent the message no one knows, but it turns out to be an invitation no one can refuse, but which everyone will regret. Inside the doors of a dilapidated mansion, they gather, eat, drink, party, and have the time of their lives - that is, until it's time to go. The front door doesn't open; the back door doesn't open. Doors that once led to familiar rooms now lead to new ones; some doors open to yet other doors, and some go straight to dead ends. Only one thing remains constant: every door is a trap, leaving only one way out.