The Boy and the Heron review – overplotted Miyazaki still delights

It’s the film that the revered animator and co-founder of Studio Ghibli Hayao Miyazaki came out of retirement to make, and it’s arguably one of his most personal. The Boy and the Heron is a strikingly beautiful, densely detailed fantasy that revisits themes and devices familiar from previous films and ties them together with elements that have a clear autobiographical resonance for the director. The dream logic of the narrative seems to have been born from the untrammelled imagination of a child rather than that of a man in his 80s. The lush orchestral score, by regular Miyazaki collaborator Joe Hisaishi, is shimmering and exultant. All the elements are in place. So it seems almost churlish to note that this is middling Miyazaki at best.

Of course, a mid-level Miyazaki film is still a vastly superior entity to much of the more cynically commercial content served up by Hollywood animation studios. And it’s not as if the seductive spell has been entirely broken. But compared with, say, the beguiling simplicity of My Neighbour Totoro, or the richly realised world of Spirited Away, this sometimes feels heavy going. Some of that trademark Miyazaki magic has been stifled by overplotted, incoherent storytelling and an unwieldy final third act.

The backdrop, for some of the picture at least, before it slips into parallel realms, is early 1940s wartime Japan. The boy of the title is 12-year-old Mahito (voiced by Soma Santoki in the Japanese original version and Luca Padovan in the impressive English-language dub). Shortly before the main action takes place, Mahito loses his mother in a hospital fire after a bombing raid on Tokyo. The inferno engulfing the city has a disorientating, impressionistic quality that’s distinct from the precise visual style of the rest of the film, and this striking image of a burning city is one that Miyazaki has cited as one of his earliest childhood memories. Mahito’s father is the boss of a factory that manufactures fighter planes (as was the director’s own father). He remarries, to his late wife’s younger sister Natsuko (Yoshino Kimura/Gemma Chan), and the still grieving Mahito is forced to relocate from Tokyo to the country estate where his mother and Natsuko both grew up. It’s a curious, cavernous place, populated by a staff of bickering, ancient crones; it comes with a lake and a bricked-up, semi-derelict tower in its grounds.

It also has another resident: an insolent grey heron (Masaki Suda/Robert Pattinson) that seems to be taking a particular beaky interest in Mahito. At the goading behest of the heron, Mahito enters the forbidden tower and finds himself drawn into a netherworld where timelines are knitted together and the infrastructure of the whole domain is controlled by some kind of high-stakes Jenga game. Fellow inhabitants of this world include Kiriko (Kô Shibasaki/Florence Pugh), a dashing sailor and fisherwoman who is skilled in magic, and the fire maiden Himi (Aimyon/Karen Fukuhara), as well as Mahito’s new stepmother, Natsuko, and a community of giant man-eating parakeets.

For a director who is so famously preoccupied with the idea of flight, Miyazaki reveals an unexpectedly complicated relationship with birds in this picture. In addition to the monstrous parakeets that eye Mahito greedily, cutlery at the ready, there is also a flock of pelicans that feed on gentle floating creatures called the Warawara. And then there’s the heron, which soon loses its elegant avian form and morphs into one of Miyazaki’s less lovely creations, a wart-encrusted, goblin-like henchman in service to the ruler of this magic kingdom – an ageing wizard who, it turns out, has a connection to Mahito’s family. Ultimately, family – even a fractured, imperfect family scarred by loss – is elevated, forming the central spine of this picture, as it does in so many of Miyazaki’s movies.

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Where this film stumbles is in its use of space and pacing. The unbounded fantasies of Miyazaki’s imagination work best if they are physically contained in some way – within the bathhouse of Spirited Away, the enchanted forest of Totoro, the castle in Howl’s Moving Castle. Here, the world in which Mahito finds himself is vast and limitless, and the director fills it – with characters, locations and exposition – until the whole film starts to feel a little cluttered. You long for a moment of stillness, an opportunity such as that offered by the bus-stop scene in Totoro, for contemplation and the chance to fully inhabit the miraculous creations of Miyazaki’s mind, rather than being bombarded by them.

• In UK and Irish cinemas from 26 December