Time Out says
The grim but gritty result brings the viewer into this hitherto clandestine world, where thousands of euros are bet on fights conducted under strict refereeing, lasting until one or both pugilists are unable to carry on. Lacking the hyped-up sound effects of familiar movie punch-ups, the footage seems almost benign at first – until we see faces tenderised like steaks and wonder why these sons, husbands and fathers put themselves through it.
Palmer struggles to impose a meaningful structure on the repeating cycle of feuding and bloodshed but he never patronises his (helpfully subtitled) interviewees, allowing us to see through their self-aggrandizing bluster. Testosterone at its most tragic.