The weirdest cousins of the already weird Marvel cinematic family, the Guardians of the Galaxy have become one of the franchise’s most loved groups. The first film was a goofy retro adventure that had no time for the self-serious side of comic book movies. The second was a bit of a mess but worked itself ragged to try to be entertaining. The third – and apparently final – outing is an odd duck. It’s sometimes funny and emotionally effective when it counts, but also very, very dark, with some of the grimmest scenes of any Marvel movie.

One thing it gets really right is putting the focus on the series’ best character: Rocket. An opening skirmish sees new baddie Warlock (Will Poulter), a golden being with Superman-ish powers and the intelligence of a toaster, try to kidnap the raccoon (voiced by Bradley Cooper), leaving him mortally wounded. When they try to save him, Rocket’s friends discover he’s been fitted with a device that will kill him if anyone operates on him. It’s a security tag. Rocket was created by someone and they don’t want anyone else getting their hands on him.

This sets up two things: 1) a race to find the person who did this to Rocket and save his life, and 2) flashbacks to his origin story. James Gunn, serving as both writer and director once again, has given himself a very difficult tonal balance here. Rocket’s backstory is miserable, full of animal torture and hideous experiments, like a raccoon version of A Little Life. The animals may be CG, but it’s a jolt to go from a bleeding cub whimpering ‘Hurts’, or a turtle being incinerated to Drax (Dave Bautista) and Mantis (Pom Klementieff) bobbing about in space making silly jokes. There are some really fun sequences, especially on a gross space station made of flesh, but the bleakness of Rocket’s story gives it all a gloomy edge.

This is Gunn’s goodbye to the series and the Marvel universe (he’s jumped ship to DC), and if much of the film is oddly paced, he thankfully lands the final moments of the farewell. Each of the characters gets enough meaningful screen time to make you love them again, and they’re all chucked together for a strong action climax, so it goes out with a firm reminder of how good this gang can be. He’s even forgiven for making a corny dance sequence work, given how central music has been to this series.

This is definitely one film made for the fans. If you’ve been paying close enough attention to clearly remember Peter’s last minutes on Earth, why Gamora is here despite dying in Avengers: Endgame, and when a talking dog joined the group, you will probably get more from this than the casual fan. The less dedicated viewer should be reasonably entertained, although maybe wish for the days when the laughs outnumbered the tears.