I wanted to be Tom Cruise.

As a fresh-faced, impressionable young 21-year-old, I watched Top Gun a dozen times at my local movie theater in London.

Cruise WAS Maverick, his fighter pilot character in Top Gun, on and off screen: a handsome, smart, funny, charismatic daredevil who got all the girls.

Today, he looks virtually the same as he did back in 1986, a veritable wonder of middle-aged vitality and good health, and still flashing that big cheeky grin.

The Tom Cruise the world fell in love with in Top Gun, left, has barely aged in nearly 30 years. Cruise is a veritable wonder of middle aged vitality and good health

What is different, and shockingly so, is what we now know about his always mysterious personal life.

And in particular, his relationship with an even more mysterious entity – the Church of Scientology.

On Sunday, HBO aired a much-hyped documentary into the cult Church, called “Going Clear”.

It was an astonishing, terrifying film; one which finally nailed many of the unpalatable truths about this deeply secretive and deeply unpleasant organization.

The movie’s impact has raged through Hollywood like a tidal wave, mainly because one of its biggest targets is also one of the world’s biggest movie stars: Tom Cruise.

But as a new documentary, the Scientologist turned his children against their mother Nicole Kidman and agreed to have her phone tapped, among other allegations

In some of the most damning allegations, “Going Clear” reveals how Cruise:

1) Allowed his children to be turned by Scientologists against his former wife Nicole Kidman in their bitter divorce and custody battle - through fears that she was a Suppressive Person, or 'SP' in Scientology speak.

2) Conspired with the Church to wire-tap Kidman’s phone as part of a deliberate effort by the Scientologists to break up the marriage. (Kidman had been further identified as a “PTS’, or 'Potential Trouble Source' because her father was a psychologist and the Church doesn’t like psychologists.)

3) Had Scientology employees work on his cars, motorcycles and living quarters at the Church’s various residences for slave labour rates of just 40 cents an hour.

4) Ignored myriad abuses, both physical and psychological, by the tax-exempt ‘non-profit’ Church - while at the same time accepting lavish gifts and honours from them..

5) Has an unsettlingly close relationship with Scientology leader David Miscavige, a man portrayed by many ex members of the Church as a manipulative monster.

In perhaps the most disturbing claim of all, the movie tells how the Church found Cruise a new girlfriend – a young Scientologist, Nazanin Boniadi.

They reportedly showed the Iranian actress confidential evidence of her then boyfriend confessing an affair, causing her to ditch him. They then gave her a sleek new makeover, had her braces removed, bought her $20,000 of clothes, and changed her hair colour to Cruise’s preference. The ‘romance’ lasted just three months before the Church ended it, after an incident where Ms Boniadi supposedly hadn’t been respectful enough to Miscavige and Cruise screamed abuse at her.

She was sent back to a Scientology centre where she confided in a friend what had happened, and was promptly punished with orders to clean out public bathrooms with a toothbrush.

The whole story is utterly sickening in its cynical heartlessness and exploitation.

But entirely consistent with many other similar stories surrounding the Church.

The depth of Cruise’s devotion to Scientology is high-lighted in two more incredibly disturbing pieces of video in the movie that have previously appeared on the internet, only to be torn down by the Church’s aggressive lawyers.

In the first, a highly-polished promo, Cruise - wearing a black turtle-neck sweater - stares straight at the interviewer in a wide-eyed, excitable, slightly demonic way, cackling insanely at various points as he talks with breathless enthusiasm about the Church.

‘Being a Scientologist, ‘ he says, ‘when you drive past an accident, it’s not like anyone else….you know you have to do something about it because you know you’re the only one who can really help. We can change people’s lives, and I am uncompromisingly dedicated to that.’

The depth of Cruise’s devotion to Scientology is high-lighted in a disturbing pieces of video shows Cruise cackling insanely at various points as he talks with breathless enthusiasm about the Church. He asserts that Scientologists have powers to rehabilitate criminals, bring peace, get people off drugs, and unite cultures

He goes on to assert that Scientologists have special powers to rehabilitate criminals, bring peace, get people off drugs, and unite cultures.

The second features Cruise receiving a top Scientology award from Miscavige, where he almost passes out from euphoria.

After watching both clips, you’re left thinking Cruise is a complete and utter whack-job.

For a long time, rumours have circulated about his weird relationship with Scientology.

Now, those rumours have been cemented in a documentary of irrefutably detailed journalistic research and sourcing.

(HBO reportedly had 166 lawyers poring over everything before the film was cleared for broadcast.)

Cruise has been silent about the HBO documentary so far, but his devotion to the church and its leader David Miscavige, pictured, is alarming

The Church, as it always does, reacted with a vicious public diatribe against the film-makers and HBO – condemning it as a pack of lies.

Denigrating opponents is their default position to any perceived attack.

But this time, judging by the horrified reaction from the public on social media (I was on Twitter when “Going Clear” aired on Sunday night and the fury against Cruise was instant and intense), it won’t work.

For Cruise, it couldn’t have come at a worse time as his once relentlessly stellar career hits the decelerator button.

At 52, and despite his still remarkably youthful looks, he can’t grab the same heart-throb roles he used to, most of his movies have under-performed in recent years, and he’s in serious danger of fast becoming a washed-up action hero.

Now he’s been exposed as a nasty piece of work conspiring with an even nastier cult to treat people like dirt and manipulate their minds.

And it threatens to destroy his reputation and career.

The star, once so verbose in his support about Scientology, has so far remained resolutely silent since “Going Clear” aired.

But that strategy won’t fly with anything like the success Maverick once did.

Tom Cruise is now facing his moment of truth.

Either he cuts off the Church of Scientology with the same ruthless selfishness he seems to have deployed in first selecting and disposing of the women in his life.