The premise of Sunshine sounds like the silly stuff of your typical summer sci-fi blockbuster. The sun is dying; mankind faces extinction. The spaceship Icarus II and its crew have been sent to deliver a nuclear bomb-like device into the heart of the sun. This should reignite it and thus save humanity.

But this is a film by Danny Boyle (Trainspotting), with a screenplay by Alex Garland (The Beach), so you can forget any kind of Bruce Willis heroics, scenes of mass destruction or shots of a grateful humanity looking up to the heavens. Sunshine is sci-fi for grown-ups, and if you’re looking for popcorn thrills, look elsewhere. There isn’t a laser beam or alien life form in sight. It belongs to that preStar Wars tradition of science-fiction films, such as Kubrick’s 2001: A Space Odyssey and Tarkovsky’s Solaris, that probe the Big Stuff: God, Reality and What Makes Us Human.

The script’s premise is an intriguing one: what happens to humanity when the sun burns out (as it is expected to do in five billion years)? Garland, however, has placed the events in 2057 to crank up the urgency. What we do when the sun runs out is a lot more dramatic than the current eco-nightmare of what we do when the oil runs out. But what bothers me about this premise is the idea that the sun is some sort of galactic domestic gas boiler that you can reignite by the match of a nuclear device. If a Jerry Bruckheimer film purveyed this theory, it would be instantly dismissed by snooty sci-fi aficionados.

Never mind. Sunshine is really about a journey to the sun that becomes a trip into the heart of human darkness. As Icarus II creeps towards its destination, cracks in the crew’s unity and discipline start to appear. A fight breaks out between Capa (Cillian Murphy) and Mace (Chris Evans). The crew have bad dreams. The ship’s medical officer, Searle (Cliff Curtis), becomes obsessed with peering into the light of the sun. What is in there — the face of God? The technology on board the Icarus will stop the ship’s wings from melting, but not the minds of its crew.

BACKGROUND

• Sunshine

• Full of bright ideas

• Sunshine on my mind

• Sex in space? Not in Sunshine

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When the ship passes into the “dead zone” — the point at which contact with earth is no longer possible — they start to pick up signals from Icarus I, a ship that tried to carry out the same mission seven years earlier, and has been missing ever since. Someone suggests making contact with Icarus I and getting hold of its nuclear device. This causes more crew conflict. Tough guy Mace believes they should stick to their mission. But, as Capa points out, they have only one chance and, well, two bombs are better than one. So they alter their course, and the trouble begins.

What is so refreshing about Sunshine is the way it constantly — at least until the ending — fails to go in the direction you expect it to. Its plot is driven by a series of accidents, goof-ups and wrong calls. The irony is that these are things that make us human beings and not machines, yet they threaten to destroy all of humanity because they threaten the mission. What follows is a series of struggles, not against life-threatening forces, but with more mundane challenges such as repairing the ship’s solar panels, rebooting the computer or putting out a fire. In space, no one can hear you do DIY.

With the exception of Cassie (Rose Byrne), the pilot of Icarus II, this is not exactly an engaging crew to spend time with. Garland could have done more to make us warm to them. And you never get a sense that Capa is burdened by the knowledge that the fate of humankind ultimately rests in his hands. Consequently, Sunshine is one of those films that are easy to admire, but harder to love. What it offers, though, is a different kind of spectacle from zapped cities or galactic battles — instead, we get a kind of fantastic trip to the planetarium. Boyle seems to be saying: behold the wonders of Mars! See the mystery of the sun! It’s good to see a space film that is actually impressed by the wonders of space. His film is stunning to look at, like a fantastic light show. Its soundtrack causes the cinema to rattle and its bright lights shake the retinas of your eyes.

My main complaint — and, I suspect, a lot of other people’s too — is that during the last 25 minutes or so, it is impossible to follow what is happening. The film loses its moorings in reality and goes into a kind of hyperdrive nightmare scenario, as if Boyle himself has gone a little nuts. And he employs the kind of alien-intruder device that he has hitherto managed to avoid, which is a terrible shame, because we get a lot of ga-ga, God-inspired gobble-degook that undermines the film’s theological speculations.

Sunshine 15, 107 mins Three stars

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