You know what would be completely different? If just for once a new Hollywood blockbuster took place in a world that was not just about to explode. You know the deal. From the count down clocks to the increasingly massive explosions, carnage is what the big studios think we want.

Now imagine going to a film where the future not only looks bright, it actually looks amazing? Nah, I didn't think you'd want to see it either.

If there's one thing that Hollywood knows that really sells it’s Armageddon. Even the Bible ends with one. It's like we all have a self-destruct timer inside us just waiting for an excuse to blow.

In Tomorrowland, opening Friday, George Clooney, the 54-year old Irish American actor with the golden era Hollywood looks and charm who first rose to prominence in ER, plays Frank Walker, a former inventor who now lives like a hermit because, as they say, he-knows-too-much. Frank was a former science prodigy who now wants to be left alone and not asked too many questions.

The person asking him too many questions is young Casey Newton (Britt Robertson), a gifted young teenage scientist who has discovered that she's being chased by murderous robots from the future, and naturally enough she wants to know why.

If that already sounds like a crazy set up, don't worry, it gets much weirder. Clooney has clearly been cast to give this whacked-out sci-fi tale some old Hollywood panache, and this he does in every scene, first as the cantankerous oldster who doesn't want to be bothered, and then as the broken hearted suitor who really does want to save the world he once turned his back on.

At root Tomorrowland is a good old fashioned Disney epic about how a spirited young girl's refusal to say die can change the fate of all humankind. It's completely laughable hokum, in other words, but it doesn't take itself at all seriously so it allows you to try.

What Tomorrowland does get right, in spades, is the creation of a story with a young girl at the center. There aren't any boys to steal her limelight or pine after; instead Casey is a can-do budding scientist who relies on herself to get out of dangerous scrapes. It's feminism for the Taylor Swift era.

When we meet Casey she's trying to help her sainted dad keep his job at NASA's about to be closed space program. Once upon a time America dreamed big and reached for the stars, but now they've closed up their rocket programs. No moon landings are in sight, and the world has stopped caring. That means dad will soon be unemployed.

To prevent the inevitable Casey sabotages the base's dismantling in a desperate bid to buy her family some time. It doesn't work. She’s soon picked up and when she posts bail she discovers a weird badge she doesn't recognize among her personal effects.

It's when she touches the badge that her life changes. Suddenly she's transported to Tomorrowland, a sort of fifth dimension mash up of Disney's Epcot Center and the 1964 World's Fair.

Monorails whizz past, people get around in Jetsons flying cars, kids get to school wearing jet packs. It's a gee whiz 1960s style brave new world of the future, and that also explains its kooky charm.

Cooney's sad eyed Frank Walker has seen this future and he's even lived in it for years before he was finally deported from coming too close to its truth. And what that truth is takes the film roughly two hours to find.

Along the way expect to be wowed by Star Wars levels of eye-popping sci-fi spectacle. Also along the way expect to try and figure out what compelled Clooney, an old school progressive in the grand tradition, to sign up for this brilliantly weird film.

Was it the opportunity to stick it to climate change deniers (he certainly does), or was it the chance to scold the endless loop of dystopian horror shows that pass themselves off as blockbusters nowadays (he certainly does that too)?

Or was it Tomorrowland's Baby Boomer 1960s style vision of tomorrow with all of its flying cars and silver space rockets that caused him to sign on? Because the truth is Tomorrowland wants to take us back to the future, but the future we used to believe in, not the one we have begun to dread.

What's not said is that America used to be Tomorrowland, but like the former paradise in the film it has lost its mojo. It's time for a little space age optimism to descend and inspire us to reach for the starts again, Disney has decided.

The real reason for Clooney's participation in this likable caper may be that he's at the stage now where he does what he wants, participates in what he chooses to, and knows what messages he wants to send.

Even in his personal life he seems to have found a level of ease unlike anything he knew before. Clooney married the accomplished barrister Amal Alamuddin in Venice last year, and told the press last week that he has never been happier about life.

“I’ve always been optimistic, by the way. Actually, I’ve had a very lucky life overall. I’ve been able to do a lot of things I’ve never really imagined I would do but it’s a very good time in my life,” Clooney said. “I’m having a wonderful time and I’m a very lucky man to have met someone as special as my wife so I’m very happy, very optimistic.”

Not even the completely unsympathetic character he plays at the film's outset put him off the script. Clooney admitted that he agreed to star in the film alongside director Brad Bird and writer-producer Damon Lindelof as soon as he read it, despite being cast in the role of a “55-year-old angry, bitter has-been.”

Working in the often real-life unstable societies like Sudan and Darfur and sub-Saharan Africa and the Middle East has given Clooney a different perspective on all the bad news blockbusters we've been seeing in our post-9/11 nation. He doesn't just want to help. He wants to bring about some hope for tomorrow too.

“You’ll see these things and feel completely inundated if you watch the news -- and you should watch the news -- but it can’t just be that,” he said.

“There has to be some positive in it. Understanding the endeavors that I’ve taken up, we know we’ll never completely succeed in. I’ll be long dead before they are solved. But participating is part of the game so I’ve always believed in that, and that was part of what attracted me to the film.”