Sharon decides on her maid of honour and Rob asks Sharon's brother Fergal to be his best man. Rob and Sharon enjoy their stag and hen nights, both of which spiral out of control.

Sharon and Rob plan their wedding while Rob plans a surprise birthday party for Sharon. Rob is fired via Skype by his Boston bosses and begins searching for employment in London.

Sharon's parents visit from Ireland and have a strained introduction to Rob. More health complications create stress for them both, and Rob's secret friendship with Chris explodes in his face.

Pregnant Sharon's hormones plague her with waves of horniness and sadness and a host of other fears. Rob begins a clandestine friendship with Chris, who is married to a woman Sharon can't stand.

Sharon faces the reality of having a new room-mate in the form of Rob, the man whose child she happens to be carrying. She introduces him to her brother Fergal who gives them both a royal hard time.

Can Sharon, 'an extraordinarily good-smelling woman', and Rob, 'a sturdy love-maker', navigate the thorny situations they find themselves in and still find time for an emergency shag in a stairwell?