I should start this with a disclaimer: I saw How to Train Your Dragon 3 in Dutch (Flemish, if you want to be pedantic). The voices were done by different actors and I may well have missed some of the jokes. If my Dutch completely fails me, it may also be possible that I saw a completely different film to everyone else. But here goes anyway.
The film opens on the isle of Berk, which Hiccup has turned into a utopia in which dragons and humans can live together, but all good things must come to an end. In this case, we have two main developments to turn things around. The first is the arrival of a Light Fury — a female counterpart to Toothless. The second, darker, event is the appearance of Grimmel, a particularly villainous dragon hunter.
So Hiccup must find the fabled Hidden World so that his dragons can finally live in peace.
This is not a particularly dense plot and Grimmel is not a particularly interesting villain. But none of this really matters as the narrative exists primarily to allow us to spend more time with Hiccup, Astrid, Toothless and the Light Fury. And here, the film really comes into its own.
Visually it’s stunning and the courtship between Toorthless and the Light Fury is beautifully handled and a joy to watch. This is reflected in a growing closeness between Hiccup and Astrid, all of which serves to set up a suitably emotional ending.
Of course, there is plenty of humour to enjoy and the scenes involving the dragons are suitably spectacular. Ultimately, though, this is a film about letting go and moving on and it handles this in a way that works well for both adult and younger audiences.
All in all, this makes for a wonderful ending to the trilogy and a satisfying completion to the story of Hiccup and Toothless.