D-Effects (2014)

A group of friends from London, Callan, Rachel, Marcus, John and Mariah, are experiencing the death of Callan during his birthday party at Mariah's house. Each of them have a good reason to have killed Callan, but none of them remember what's happened since they all passed out during the party after taking lots of drugs and alcohol. Mariah's house is completely locked from the inside and the survivors can't get out. They will start to understand what is happening to them and investigate who is Callan's killer.