Derry Girls review, season 3: Lisa McGee’s electric depiction of adolescent monomania is back for one last time

“They told us we were young,” a breathy voiceover declares, in a pronounced Northern Irish accent, “yet we understood the enormity of it. We understood what was at stake”. These opening words – especially with Saoirse-Monica Jackson’s trademark quiver on the word “enormity” – would be enough to thrust the viewer straight back into the world of Derry Girls, even if they weren’t being played over home video footage of the show’s central cast, intercut with balaclava-wearing riflemen, burning vehicles and rosary beads. This is the Derry of the 1990s, the backdrop against which Lisa McGee’s rightly acclaimed sitcom plays out.

The show’s third and final season begins with the gang of schoolmates attempting to replicate the success of some East German teenagers, by making a short film about the Troubles. Though it’s really a throwaway gag designed to introduce the episode’s main plotline – the girls preparing to receive their GCSE results – it’s typical of how the show handles its context. Derry Girls is neither about, nor not about, the Troubles. Instead, it’s about the resilience of human vanity and self-absorption in the face of the greatest challenges. In the same way that M*A*S*H demonstrated its characters’ capacity to be drunk and disobedient, even under constant threat of shelling, Derry Girls is an electric depiction of adolescent monomania.

If there’s one complaint commonly raised against Derry Girls, it’s its brevity. In existence (until now) are a sum total of 12 episodes, running at 25 minutes a pop. But this very British approach to series lengths does allow Derry Girls to pick-up precisely where it left off, without requiring much off-screen character or plot development. Erin (Jackson) remains an out-of-control narcissist. Clare (Nicola Coughlan) continues to be a neurotic mess. Michelle (Jamie-Lee O’Donnell) has learnt nothing, while James (Dylan Llewellyn) is still English and Orla (Louisa Harland) still Orla. Those dynamics, beautifully balanced after the first two seasons, aren’t worth tinkering with. “We’re girls. We’re poor. We’re from Northern Ireland and we’re Catholic for Christ’s sake!” Clare proclaims, fearing that failed GCSEs will result in the end of the known universe. It’s as close as McGee gets to going full Alan Bennett; the rest of the farce is pure Molière.

While continuity is the name of the game, Derry Girls cannot avoid its own success. The first episode of this new series is marred somewhat by a distracting celebrity cameo (so distracting that Channel 4 have sworn me to secrecy about his or her identity), but that represents a rare deviation from the show’s tried and tested formula. No scene in Derry Girls is ever very far away from a return to Erin and the gang’s shenanigans, or the wider goings on of the Quinn/McCool clan, such as harassed Mary (Tara Lynne O’Neill) and wide-eyed Sarah (Kathy Kiera Clarke) lusting over the same plumber, or hapless Gerry (Tommy Tiernan) helping his brutish father-in-law (Ian McElhinney) bury a murdered rabbit.

The episodes are so short, Derry Girls can feel frustratingly moreish. But McGee has inflected the show with such a sweet, endearing sense of chaos, that the plot never really has to be resolved. The end credits, and that bubblegum splash of Nineties pop, relieve the friends of any real responsibility for their actions. That is the fairytale quality of Derry Girls: we all recognise the hysterical pitch of teenage emotions, but the stakes are kept reassuringly low. The peace process rumbles on in the background with the abstract grandeur of history; in the foreground are all the other, much funnier, troubles associated with growing up. Nothing of importance ever happens, but that nothing happens very importantly.