Matthew, Tom and Ben enjoy their bank holiday tradition of late nights, strong cider and knock-off board games. However, their game of Propertyopoly becomes all too real when they accidentally massively overdraw on their joint account.
With the banks closed till Tuesday the boys attempt to keep their unauthorised withdrawal of £5,000 from burning a hole in their collective pocket. Matthew wants to lock the money away. Tom wants to speculate. Ben wants to order a mountain of takeaway food.
Rachel meanwhile has her own adventurous weekend planned. Andrew's work has arranged a murder mystery weekend and she's off to guess who done it, leaving the boys to protect the cash.
The simple task of not spending money is proving too tricky for the badults. As the cash ebbs away Tom takes the advice of local bookie Aggressive Gary and turns to the gee-gees. Matthew draws up a business plan, but Ben spies an opportunity for riches in one of Tom's smellier ideas.
Tensions rise and friendships unravel, eventually plunging the flat into civil war. Territory is divided, barriers erected, an aristocracy formed and peasants enslaved. All that remains is revolution. Will Rachel return in time before someone really loses their head?