Jia Ling writes, directs and stars in this boxing drama with a twist: there’s not really very much boxing in it. In this smash hit from China, we’re introduced to Du Leying (Jia) as a no-hoper; the perspective, in fact, of the supporting characters and the film itself is that it would be hard to imagine a bigger loser. She’s 32, lives at home, doesn’t adhere to traditional beauty norms (particularly as regards body weight), and her boyfriend is cheating on her with her best friend. When this affair is discovered, the best friend heaps another item on the laundry list of putative indignities that make up Leying’s life by immediately asking her to be a maid of honour at the wedding. But as far as we can tell, she has been living her life as if she has been recently dumped for a really long time anyway, and the film takes its sweet time showing us the catalytic change we know is coming. At around the 45-minute mark, she goes to the gym for the first time. You could probably compress everything that happens in that first 45 minutes into 10 without losing any crucial narrative or cutting any of the occasional, limp jokes. Once she gets to the gym, the point is further belaboured: she is surrounded by slender lissome young lovelies flirting with their enthusiastic personal trainers, whereas she is – surprise, surprise – less popular. About an hour into the film, she goes to a supermarket and puts some healthy food in a shopping trolley. A little later, she punches a sleazy colleague in the face. There is still, somehow at this point, almost half an hour before the montage we know is coming, of Leying seriously training and losing weight and getting into boxing. There is something striking about seeing the real-life actor lose 50kg (7st 12lb) across the course of the montage but, as with all such sequences, it won’t be for everyone. One person’s inspirational personal journey of extreme transformation is another person’s triggering affirmation of diet culture in a society where it’s hard to escape the message that thin is king. As a document of a physical transformation, the film delivers. As a comedy or romance, not so much.