Irish schoolteacher Sharon meets American advertising executive Rob in a London bar. They quickly learn that Sharon's pregnancy is just the first of many problems they’ll encounter.

Sharon faces the reality of having a giant new roommate in the form of Rob, the man whose child she happens to be carrying.

Pregnant Sharon’s hormones plague her with waves of horniness and sadness and a host of other fears. Rob begins a clandestine friendship affair with Chris, the husband of a woman Sharon can’t stand.

Rob’s secret friendship with Chris explodes in his face in a way he could never have imagined, and Sharon receives a visitor.

Rob is fired via Skype by his Boston bosses and begins searching for employment in London with some extremely “strings attached” help from his friend Dave.

Rob and Sharon split up to enjoy their stag and hen nights, both of which spiral out of control.