While much of Marvel’s output has rather blurred together of late into a gaudy onslaught of overplotted multiverse-hopping, the Guardians of the Galaxy movies have, for better or worse, always had a distinctive personality. What elevates Vol 3 (supposedly the final film in the GOTG series) is the way it keeps that personality, nodding to the irreverent swagger that is a crucial component of the Guardians USP while delivering a series of devastating emotional sucker punches along the way. To achieve this, director and co-writer James Gunn takes the fail-safe, heartstring-twanging route of placing adorable animals in peril, exploring Rocket the raccoon’s traumatic backstory, and touching on some unexpectedly dark themes – eugenics and vivisection – in the process. There’s a kinship with Bong Joon-ho’s Okja: both pictures celebrate loyalty and friendship while also acknowledging humanity’s capacity for unimaginable cruelty to other species. As a young, impossibly cute kit, Rocket (voiced by Bradley Cooper) fell into the hands of the High Evolutionary (Chukwudi Iwuji), a mad scientist with a God complex who believes that a perfect society starts in a macabre animal-testing laboratory. Rocket escaped, but in doing so he was separated from his soulmate, Lylla (Linda Cardellini), a pure-hearted otter with prosthetic metal arms. Now the High Evolutionary wants to recapture his most successful experimental subject, and he sends beautiful, gilt-edged dullard Adam Warlock (Will Poulter, great fun) to reclaim the raccoon. Classic rock needle drops and showy, snaking, single-shot action sequences – both GOTG trademarks – abound in a picture that balances a slightly overstuffed storyline with mischief, humour and the biggest of hearts.