Irish comedian Danny O’Brien returns to the Fringe with a new show about going to prison – as a performer, not an inmate. The natural storyteller weaves a tale about playing to the toughest crowds imaginable (literally) with anecdotes about tour life, family and passive aggressive neighbours.

Despite the late start time, O’Brien gives an energetic performance and although this is stand-up, standing still is something he rarely manages. Audience interactions produce some hilarious results, down to a combination of the comedian’s ability to size up the crowd and the well-oiled punters being open to a piss taking.

The comic explores the logistics of doing gigs in prison and finds it’s harder to get into jail than you would think. He visits abandoned prisons to get a feel for life “inside” and discovers more spacious living quarters than you would find on Airbnb during the Fringe. The room Lock-In takes place in at Underbelly Cowgate has a dungeon-like quality which only adds to the incarceration theme.

A regular on the festival circuit and fresh from a six-country tour, O’Brien achieved a career highlight in June, opening for US comedian Bill Burr to a crowd of 7,000 in Dublin. He takes the audience through the build up to the gig and the after-party, which lead to another kind of lock-in. The next day, while nursing the mother of all hangovers, he realises he has a prison gig that afternoon and blunders from one disaster to another, while trying to honour his commitment.

As the show reaches its climax the laughs intensify, even managing to drown out the festival fireworks, and the audience leave grinning after spending an hour in the presence of a performer who seems to genuinely enjoy what they do.