Peter Jackson knows a thing or two about science fiction, fantasy, and imaginative and metaphorical stories. Lord of the Rings was an epic saga, not only for the story based on the undisputed and moving genius of J.R.R. Tolkien, but also in terms of the colossal proportions of the productions.

Therefore, if Jackson takes on a science fiction project, it is clear that we are intrigued, that we want to see it first-hand, find out more, above all if the subject is a new adaptation of a book and Jackson’s co-writers are his wife Fran Walsh and Phylippa Boyens, the screenwriters for the Tolkien saga, with seven Oscar nominations, three of which they won, under their belts.

So here we are, sitting in our red cinema seats, ready to see Mortal Engines, a film which seeks to follow in the wake of the huge success of Hunger Games.

One of the fundamental and most captivating aspects of science fiction is the context, the arena in which the story takes place, a world with its own geographic, political and social rules which, as either spectators or readers, we have to enter.

The arena of Mortal Engines is interesting. Around the year 3000, the planet Earth has survived the sixty-minute war - which was all the time necessary to destroy a large part of the world with quantum energy weapons. The continents have been pressed together, North America is a radioactive desert, while Europe, Asia, Africa and Oceania are united, but separated by a wall, a symbol of all devastating divisions in both fantasy and the real world: to the East the permanent cities, to the West, mobile cities, which move in search of resources in a world which has been completely impoverished and in which the only rule is homo homini lupus.

Technology has taken a step back, or more precisely, it has disappeared. Humankind has returned to iron, to coal, to steam (and here is the link with Steampunk).

It is these self-propelled cities, headed by London, which are the most interesting aspect of the film. They resemble gigantic versions of the walking castles of Miyazaki (Howl’s moving castle, Spirited away), cities with multiple levels that correspond to social levels and new guilds, which run on caterpillar tracks, travelling the world and devastating the land, or which fly through the sky (here again we are reminded of Miyazaki’s creations in Castle in the sky), move under water or underground, with shapes recalling creatures from the natural world like crabs or worms, appearing almost biodynamic.

In particular, London is striking in its appearance as a kind of self-propelling folly, in which iconic elements such as the underground or St. Paul’s Cathedral have been reworked in new and eccentric ways, in layers, as was the case with 18th century Venetian classicism.

It is in this setting that the story takes place. A young woman (Hera Hilmar) is seeking personal revenge, a young man (Robert Sheenan, outstanding in the British TV series Misfits) is trying to save his skin, and the two end up saving the world when the armistice between the East and West comes to an end, kind of falling in love at the same time, although their kiss has been saved for the next episode.

This leads to us to feel that the story is not the main focus of interest in the film, or at least this is what transpires from the way it has been adapted for the cinema. The impression is that the books, while aimed at young adults between the ages of 10 and 15, have a complexity and depth that the 100 million dollars invested in the production of the film have not managed to render with sufficient passion.

One of the merits of science fiction and young adult literature (two fields which are often, but not always, combined) is their metaphorical focus on important themes.

Here in Mortal Engines such themes are the sustainability of our lifestyles, energy saving and attention to environmental issues.

How will we end up if we do not take care of our planet, continuing to mistreat and exploit it? This is the underlying question in the plot, and it is an important one, which urgently seeks answers from us and our real and contemporary world.

What surprises is the realisation that nowadays, sustainability and energy are the two spectres which risk threatening the world as was the case with the atomic bomb during the Second World War, a nightmare which has greatly conditioned popular culture, particularly in Japan, where it has defined genres of film and anime, such as the much-loved sagas of robots from the 1960s, 70s and 80s.

Science fiction in its various forms has the notable merit of presenting important issues to a young audience through the filters of fantasy and visual creativity. Of course, if the film were also absorbing, then we would have everything!