Whilst nursing The Hangover from Hell Ellen discovers the kitchen filling with water.
After a desperate attempt to find the fuse box, flatmates Ellen, Alexa and Jack become trapped in the attic with Ben, Alexa's date from last night.
As the hours pass, Ellen nurses her sore head, Jack plans a rescue whilst Ben and Alexa get to know each other.
But, to everyone's horror, Ellen realises she used to date Ben at school.
Can these flatmates escape the attic? Will they be able to look each other in the eye again? And will Jack please stop live-tweeting this fiasco.