The Fantastic Four: First Steps is determined to sell the idea of heroes that a world can get behind, and Marvel hopes that audiences can too. An opening ‘television recap' gives us a brief refresher on the Fantastic Four's origin, and then bombards us with their heroic successes. Classic villains get cameos in a medley that gives us a real sense of the team, the family, and the force for good. In short, things are fantastic, but the universe won't let things stay that way.

On Earth-828, it's been four years since Dr. Reed Richards (Pedro Pascal), his wife Sue Storm (Vanessa Kirby), brother-in-law Johnny Storm (Joseph Quinn) and best friend Ben Grimm (Ebon Moss-Bachrach) were bathed in cosmic rays and granted incredible powers. Since then, they've led the world into a new era of international cooperation from their New York HQ, and even helped kids get more interested in science. They are the Fantastic Four, and they are admired and adored by all, even, grudgingly, the leader of Subterranea, Mole Man (Paul Walter Hauser).

But the arrival of an intergalactic silver herald (Julia Garner) threatens the FF's utopia: Galactus (Ralph Ineson), the Devourer of Worlds, is heading for Earth on his never-ending mission to feed his eternal appetite. The only thing that can stop him is Reed and Sue giving up their baby son Franklin, which isn't going to happen. As the world faces up to the fact that their great heroes might not be able to save them, the FF desperately try to find a way to stop the giant space god coming their way.

Unsurprisingly, the film's title works on several levels, including Marvel Studios' return to basics. First Steps recalls the franchise's old gift for weaving different genres into instalments – this time ‘60s B-movies. It's a tremendous canvas that director Matt Shakman uses to nod to epic cinematic sci-fi – 2001, Interstellar – as much as the cosmic awe of Stan Lee and Jack Kirby's original comics.

The production design is gorgeous. Jack Kirby's spirit runs through the film all the way up to a delightful late reveal and while the MCU's baulked at his gaudily brilliant cosmic vision before, this is a strong, if not totally wacky, attempt to bring it to the screen. It recalls the rush of Thor first introducing cosmic wonder to Phase One – the FF's first escape from Galactus is a particular thrill ride that gives each member their moment to shine.

Back on Earth, the film presents a dazzling blend of 1960s chic and retrofuturism. The chrome and blue buckles pop, and Manhattan looks just as fantastic when Ben Grimm stomps the streets picking up groceries and teasing school kids, as when Galactus comes calling.

Ineson is as perfect as the kaiju-sized space god as expected: all wry smile and that voice. While opposite him, the main cast each add pathos to their characters, pulling traits from comic pages to juggle domestic and superpowered challenges. It's hard to single one out, but Kirby's Sue, as mother, protector, and let's face it, most powerful of the FF, is a jolt to the franchise MCU as electric as Florence Pugh's Yelena.

The spectacle and science – Pascal's Reed navigates the equations relatively painlessly – are important, but nothing beats family. Franklin Richards wasn't introduced until seven years into the FF's comic journey, but is wisely included here. In a film pointedly about the unknown bringing fear and radical change, the link between becoming first-time parents and confronting immeasurable intergalactic power works well.

Michael Giacchino, who is possibly having the most fun of everyone, backs everything with a joyful score that embroiders that sense of family with the FF's celebrity and derring-do.

If there's a downside is that First Steps is a simply effective film because it breaks away from the main continuity Marvel has developed into a convoluted mess. That old multiversal get out of Earth-616 card. It's going to take a chalkboard of Mr Fantastic's equations for Marvel's First Family to infect the broader MCU with a similar buzz, but as a standalone debut picture to kickstart Phase Six, First Steps pops like a cathode-ray tube TV.

The Fantastic Four: First Steps is in cinemas now