The marriage of Danny and Hannah spectacularly crashes during the reception when the bride's best friend tells the groom that the bride is having an affair with her husband! The shock wave of chaos that spreads out from this one event touches the lives of a diverse group of the thirtysomethings that inhabit the Camden Town area of London. Hannah immediately leaves the reception and gets drunk and ends up in bed with the unwashed artist Cameron who shares a flat with a nerdy comic book enthusiast Liam, who in turn starts an ill-advised affair with society dropout single-mother Sophie. Danny meanwhile moves on and embarks on a relationship with a struggling singer Mary, whom he met at the airport on his way to his lonesome honeymoon. This partner-swapping merry-go-round continues for two years until a semblance of normality asserts itself and Danny and Hannah decide to drop everything and embark on their long delayed honeymoon.