April and the Extraordinary World is not as well-known as it should be. When I consulted the film's UK Wikipedia entry a few days ago, French comic artist Jacques Tardi's name was not mentioned even once in the almost 900-word article (I've rectified that).

While the film is not based on a Tardi album, his work is the inspiration for it, and he laid the visual groundwork, characters and look and feel that the producers and animators followed (much of which can be seen in L'histoire d'un Monde Truqué, Casterman, 2015). Its origin lies in a proposed WWI film writer Benjamin Legrand and Tardi planned to make but which never got off the ground. The two had worked together before, on the strip Tuer de Cafards (Cockroach Killer, 1984) and now Legrand wanted to come up with a scenario full of the things Tardi loved to draw, to wash away his sour experience from the WWI project.

Legrand created a uchronic adventure story with a nod to the Paris of the Belle Epoch, with a large dash of Adel Blanc-Sec (the film's heroine, April, is a little like her, but not as stony) and Le Démon des Glaces (The Arctic Marauder, 1974). The initial idea was for a TV series, but when it happened to come before Franck Ekinci, who had just made Marjane Satrapi's Persepolis (2007), he insisted it should be a feature film. Although Tardi did again experience the frustration and dashed hopes of delayed production, the film eventually got made and saw its premiere at Annecy in June 2015.

And it's a fantastic piece of work, up there with the best of Miyazaki. From the wonderful detail of the title credits that settle you firmly into time and place, to the cast of well-rounded characters (including Darwin, the talking cat), to the constantly driving pace from frying-pan to fire and back again.

The world's chronology splits from our own when the 1870 Franco-Prussian war is averted with the unexpected death of Napoleon III. Connected with this, the world's top scientists start to disappear, leaving a sooty world bereft of technological advancement except for its reliance on coal and steam, leading to the great Canadian Charcoal War. The setting is fantastic - the double Eiffel Tower, the international cable transports, the pedal-powered air balloons, and a house that springs legs, somewhat reminiscent of Ghibli's (and Wynne Jones') Moving Castle (2004) or a Baba Yaga's hut.

The French title, Avril et le Monde Truqué, translates more correctly to April and the Fake World, but it untwists itself and reconciles with our own timeline again by the end, with the destruction of one of the Eiffel Towers, the (perhaps questionable) benefits of electricity unleashed, and something a little odd going on with the moon.

The film has just the right balance of character, action and tension, all with an ending that gives a little emotional jolt. It survives repeated, even regular, viewings, and for fans of Tardi, I don't think it could be more perfect. Perhaps the only reason it's not on more people's radars is the French language (though it doesn't suffer at all in its English dub) - but for me that just adds even more atmosphere to an extraordinary world I'd love to keep exploring.