It’s a surprise that – to my knowledge – there hasn’t been a film like Fighting with My Family before. Wrestling is big business nowadays, and a film about the rise of a popular WWE wrestler – in this case, English-smalltown-wrestler-turned-Divas-champion Paige (Florence Pugh) – is the perfect package for both a compelling success story and an effective bit of ‘brand extension.’ Adapted from the similarly-named documentary, The Wrestlers: Fighting with My Family, this film pairs crowd-pleasing comedy with underdog dramatics. It’s a winning, if not entirely original, combination, succeeding off the back of sharp timing from writer/director Stephen Merchant and Pugh’s committed performance …but, crucially, stumbling as it reaches its all-important climax.

But let’s backtrack to the beginning. Paige – then going by either her real name, Saraya-Jade Bevis, or her wrestling name Brittany – has wrestling in her blood. Her parents (Nick Frost and Lena Headey) own and operate their own ramshackle wrestling operation, ambitiously titled the World Association of Wrestling (WAW), with daughter Saraya and son Zak “Zodiak” Bevis (Jack Lowden) the star attractions. Merchant deftly splits the difference between finding laughs in the family’s rough-edged background (Saraya’s father served time for armed robbery, while her brother still languishes in prison for assault) and fostering real warmth in their makeshift community.

The real story begins when Zak and Saraya are selected to try out for the WWE development program; Saraya makes it …and Zak does not, introducing the first major conflict of the story as his resentment and jealousy begins to fester. Further drama ensues as Saraya – now adopting the Paige moniker because Brittany was already taken – struggles to fit into NXT training sessions defined by early mornings, gruelling training regimes and perfectly-tanned models. Her trainer, Hutch Morgan (Vince Vaughn), defines her Florida lifestyle, pitched somewhere between a sympathetic father figure and the drill sergeant from Full Metal Jacket.

For a while, Fighting with My Family flirts with glamourising punishing training regimes and demonising image-obsessed Americans. Initially, Saraya feels like a failure because she isn’t a fit as she needs to be, and even trades her raven-haired gothic look for an orange tan and bleached hair to try to feel included. Thankfully, the screenplay is more nuanced than it first seems, acknowledging that relentless training has its downsides and that blonde hair and perfect abs don’t always correlate with brainless bimbos. The training needs to be difficult for the simple reason that we need our protagonists to work hard to overcome their obstacles in these films – but it can’t be too gruelling, or we might think poorly of the WWE organisation that happens to be funding the film.

Unlike most underdog sports stories, this can’t just be a story of how our plucky heroine comes to terms with her own personal demons – her self-doubt, her brother’s envy, her parents’ ambitions – because wrestling is about more than being the strongest, the fittest, the fastest. I may not follow wrestling, but it’s easy to see from the celebrities that come out of the WWE system – Dave Bautista, John Cena and of course Dwayne Johnson, who executive produced this film and makes a couple quick cameos – that a strong personality and a recognisable brand are more important than the size of your muscles (though they’re presumably more important too). And it’s here that Fighting with My Family loses the thread of its narrative a little.

The film doesn’t forget that Saraya needs a personality to succeed. During training, they practise smack talk and big speeches while continually being reminded that they need to win over the audience to convert a WWE appearance into a career. Initially, as Paige, Saraya can’t manage to convey that sort of compelling personality. In her first big fight in the NXT, she freezes up and earns a chorus of boos from the audience; part and parcel of the underdog, come-from-behind storyline, of course!

However, when we reach the climax, when the big WWE bout finally occurs, when Saraya has theoretically come to understand both herself and who Paige needs to be … she still freezes up! Not only is this an inaccurate depiction of real events, it’s a baffling contradiction of everything that the film has led up to. Sure, Paige wins her first fight, but given it’s already been established in the film that the results of a wrestling match are predetermined, we’re left baffled as to why. It’d be a different story if Fighting with My Family sidelined the realities of wrestling for a fantastical take where wrestling is fair rather than fixed, but it goes out of its way to underline these very realities. We should be celebrating Paige’s ascent in the climax, not pondering how she convinced producers to let her win the Divas championship without any in-ring personality to speak of.

This is a critical flaw, but not one that scuppers the film entirely. The film still manages to produce all those hair-raising, fist-pumping moments that good underdog sports stories should deliver. It’s just a shame that the climax – traditionally the best moment of such films – comes across as underthought and undercooked.