Gary and Terri's wedding in Ireland is finally here. The wedding party arrive at the castle of their dreams to find... that there is no castle. Wedding planner Kay has fallen victim to a fake AirBnB scam - what do you expect when you pay outside the app? - and suddenly Gary has to contend with the fact that the wedding is tomorrow and they don't have a venue. Not to worry though - Kay's on the case, and they're determined to find a new venue before anyone else finds out what's gone wrong.

The wedding party check into their hotel, but as Gary was meant to be staying at the castle, he has no room. And the manager at the hotel is, shall we say, less than helpful. The 'sten do' (that's stag and hen do, natch) is going ahead regardless, despite Gary being unable to take part as he's trying to sort out the lack of wedding venue. But the party goes on around him, and as everyone else gets drunker and rowdier, Gary gets more and more stressed - and Kay is not exactly helping.

Kay does manage to find another castle - or rather, the ruins of one. Gary can't see how it could possibly be transformed into a wedding venue by tomorrow, and sacks Kay as wedding planner. As the 'sten do' rages on, Gary's on his own, with only some castle ruins where his wedding should be. How's he going to get out of this one?