On the night before his wedding an exec is tricked into going to a party. While there, he drinks too much and ends up falling into an open manhole. When he wakes up he finds he is unable to get out, worse it's starting to rain.
How you react to this film is going to be determined by how well you can suspend disbelief. Can you completely and utterly turn off your brain and go with what the film is showing you? I mean can you just accept what ever the film throws at you regardless of how little sense it makes? If so then this is a going to be a hell of a ride. If not you are going to be cursing the filmmakers because this would have been truly kick ass in better hands.
Honestly I like the film, but I don't love it. It's a film with a killer premise that is kind of let down by the details. The look of the set raises more questions about why our hero doesn't do certain things that might get him out (why can't he climb up the ladder as shown?). Additionally there are plot turns that don't make a lot of sense. Worse several things seem to happen just to provoke reactions or keep things going to get us to the end.
This a film you watch with friends while you have drinks and you talk to it.
Worth a look, while drinking.
Personally I want a do over with a different creative team.