Help Remembering a Movie Title?

I'm trying to remember the name of a movie, so I'll give you what I remember about it. It starred a group of people who woke up in an empty house. A mysterious man tells them that the last to stay alive wins like $1 million or something like that. At first, they're all freaked out, but fine. Eventually the stress gets to them, and they eventually start killing each other, accidentally at first, but full on bloodbath murders towards the end. I remember the ending being a girl (I THINK) getting the money; she walks through the "front door" clutching the money and crying and such, and when she steps through the door, she sees like 10 other people that look the same as her: scared, shaking, sobbing, and clutching a large duffle bag of money. And they're all back in (what looks like) the same house/room the movie started in. As far actors, I only remember Dennis Hopper playing...an Irish priest I think? Please, if you know the name, tell! Thanks!