PATRICK Stewart, originally from "God's own county" of Yorkshire, spent 17 years in the US. During that time he starred in 178 episodes of Star Trek: The Next Generation and six movies (two X-Men and four Star Treks). By any standard, he had a fabulous time.
But for all that, the actor is delighted to be home. He returned to the UK last year and he just can't stop raving about it. Stewart, whose partner is 26-year-old actress Lisa Dillon, says that "on Sunday, my partner and I were driving up to Stratford-upon-Avon from London, and two or three times on the journey, I just stared out of the window and said, 'look, England.' She's getting quite used to hearing me say that now!"
Stewart and I are sitting in the second-floor bar at the London Studios, a grand office block with views over the Thames. He makes for invigorating company. The gleam of his domed head is matched by the glint in his eye.
Stewart looks like a highly orthodox, respectable man of the world, yet he clearly possesses a mischievous quality evidenced by the pink and yellow striped socks peeking out from the hems of his brown corduroy trousers. He is far removed from the clich of the earnest actor who takes himself too seriously.
Suffering no apparent ill effects from an angioplasty procedure 18 months ago, he looks fit and could pass for a decade younger than his 65 years.
So what brought him back to Britain?
"It could be crudely summed up in one word: homesickness," Stewart says.
"Late one night when I was driving home from the studios in California I put on 91.5KUSC, one of the classical music stations. They were playing a piece of Elgar. I had to pull over because I couldn't see to drive, my eyes were so full of tears. I sat in the car sobbing with homesickness.
"For a number of years I'd been pining for Britain and my romance with LA was beginning to wear thin. It's a city obsessed with the film industry and gradually that was becoming less and less appealing to me."
Going on a UK national tour with Ibsen's The Master Builder in the summer of 2003 was what finally convinced Stewart to return home. He recollects that "my heart was completely won back, and I knew I wanted to try and pick up where I'd left off in this country. I was hoping I could say 'the last 17 years never happened,' but I knew that was not possible.''
The other factor pulling Stewart - a lifelong Labour supporter - was his mounting distaste for the direction in which American politics was moving. "I was becoming increasingly uncomfortable paying my taxes to a California state government run by Arnold Schwarzenegger and to a federal government run by George W Bush."
Just what is it about being back in the UK that so thrills the actor? "It's like an electric current running through me," he says. "Britain gives me the minute detail of everyday life. What do I mean by that? When I woke up in the Pacific Palisades, the first thing I would see would be the orange blooms on a hibiscus bush. It was fabulous, but it was the same all year round.
"Every morning that bush was reminding me that I was not in Britain. I was an alien in a foreign land. Then I'd turn on the radio and listen to National Public Radio. It was good, but it wasn't Jim Naughtie. Whenever I tried to explain to friends what I was missing, they'd look at me as though I was crazy.
"But it's the subtlety of life that you don't have in the US. I had a wonderful, easy and at times glamorous existence in California, but the detail of my past and my background just wasn't there. I missed that shorthand of a relationship with a country. The US might be the most exciting country on the planet, but I just don't have the intuitive relationship with it that I have with Britain.
"Now I'm back here, I have constant stimulation - look where we're sitting right now," he says, gesturing at the majestic sweep of the Thames that stretches from the Houses of Parliament up to St Paul's Cathedral.
"I know that I'm continually being fed by all this and stimulated creatively and socially," Stewart continues. "It's like re-starting a love affair with this country."
He also feels reborn professionally. He has a slew of projects about to hit the stage and screen, starting with Eleventh Hour, a gripping new ITV1 series in which Stewart plays Professor Ian Hood, a fearless government scientific adviser.
Over the course of four feature-length episodes he tackles issues such as human cloning, the outbreak of a deadly bug, global warming and a possible cure for cancer. The series has taken inspiration from the headlines, and has a real immediacy.
Stewart is quick to assert that, despite his previous role as Captain Jean-Luc Picard of the Starship Enterprise, Eleventh Hour is about science, rather than science fiction. "It has nothing to do with science fiction whatsoever. No aliens anywhere in sight, no space-time continuum.
"Science has the opportunity either to play a brilliant, life-affirming part in our existences or to crush us completely. I'm not scientifically minded myself, but what intrigued me about Eleventh Hour was the idea of taking a variety of different issues - some of them, like cloning, quite complex - and turning them each into a riveting, 90-minute investigation.
"We're not lawyers, doctors or police officers - that ground is already very well covered by TV drama - but we tell page-turning stories that I hope will grip people. I hope they'll want to know what happens next, while being introduced to the moral philosophy side of science. There's so much that's frivolous on TV these days. This appealed because it has real substance."
Playing opposite Stewart in Eleventh Hour is rising Scottish star, Ashley Jensen. The 36-year-old from Annan takes the role of Hood's Special Branch bodyguard, Rachel Young. She and the scientist have a close, sometimes flirtatious relationship, based on that staple of so many TV dramas: Unresolved Sexual Tension (UST, as it is known in the trade).
Quite by chance, Stewart and Jensen also teamed up last summer in Extras, Ricky Gervais and Stephen Merchant's BBC2 comedy about Andy (Gervais) and Maggie (Jensen), a pair of actors destined to careers as non-speaking "supporting artists". The series has been the making of Jensen - her brilliant performance as the hapless Maggie won two gongs at the British Comedy Awards last month.
In one memorable episode, Stewart appeared as a fictionalised version of himself, rehearsing for a production of The Tempest and being interrupted by Andy begging for help in securing a speaking part.
In real life, Stewart has been booked to play Prospero at the Royal Shakespeare Company later this year. "Some people might think I'm only doing it as a spin-off from Extras," the actor says, chuckling.
He recalls how he came to land the part. "One day, out of the blue my mobile phone rang while I was wandering around a market. 'Hello, Patrick, Ricky Gervais here. How would you feel about being in Extras?' I thought, 'Someone's having me on here.'
"Was I worried about being ridiculed? No, I was immensely flattered to be asked and said yes before even seeing the material. When I did read the script, I knew I'd made the right decision. How often do you get to work on a brilliant, cutting-edge sitcom with one of the true geniuses of British comedy?
"During some episodes of Extras - like the one with Les Dennis - I almost wanted to look away. One minute I felt I shouldn't be watching; the next, I was slapping my thigh with laughter. To have the opportunity to appear in something like that was just unmissable."
Born the son of a Parachute Regiment sergeant major in Mirfield, Stewart was the youngest of three brothers. After graduating from Bristol Old Vic drama school he enjoyed many years as a well regarded but hardly famous stage actor.
All that changed in 1987, however, when at the age of 47 he was offered the role of Picard. The actor is pleased that he was catapulted to global fame at this relatively late stage in his career. "I'm grateful that the kind of success I had came when it did. I was just about well balanced enough for it not to be overwhelming, and not to believe the publicity. That's the biggest danger, you see: believing that you really are more important than everyone else. We're not, you know. We're just actors."
He rejects the notion, put about by more sneering elements, that he was somehow "dumbing down" by taking command of the Starship Enterprise. "They used to ask me, 'why, why, why?', as if I was somehow slumming it. It was ridiculous to suggest that I was betraying my background. What crap! What snobbery!"
Stewart has no regrets about accepting the part and thinks the seven-year series has endured the test of time. "The other day I was in a hotel room in Vancouver. I'd just arrived from London and was flicking through the channels when, hello, it's Star Trek: The Next Generation. As I sat there watching it, the waiter came in with room service and glanced over at me.
"I thought, oh no, he's spotted me watching Star Trek and he's going to go back to his mates in the kitchen and say, 'I've just seen the saddest thing - a guy watching re-runs of himself on TV. How pathetic!' However, the only reason I was watching was because I had no recollection of that particular episode, but I thought it stood up really well."
Playing Picard has also clearly not restricted the range of roles that Stewart is offered.
"I think perhaps when I first walk in front of the camera, they'll say, 'aha, there, ah, yeah, Jean-Luc, we recognise him despite that charming little moustache.' But I believe that audiences are really smart enough to let go of that pretty quickly.
"That's also my job as an actor - to persuade them that Jean-Luc Picard is left behind and this is someone entirely different. I'm an actor dedicated to transforming myself and to creating original pieces of work, and I will not accept that my life is going to be forever connected to Jean-Luc Picard in the roles that I play."
To reiterate the point, as well as starring in Eleventh Hour, Stewart is reprising his role as Professor Charles Xavier in X-Men 3, which will no doubt be one of the summer's biggest blockbusters.
And he's voicing a regular character in the hit American animated series Family Guy and revisiting his theatrical roots at the RSC by playing not only Prospero, but the male lead in Antony and Cleopatra.
So life is evidently sweet for Stewart. The twice-divorced actor won't talk about his relationship with Dillon (whom he met on that production of The Master Builder) - he says simply that "it's off limits". She has been quoted as saying that "Patrick is a brilliant, wonderful, gorgeous man".
As he makes to leave, the actor underscores how happy he feels right now: "I have a smile on my face every morning when I wake up."
Perhaps for Stewart, this period is a reminder of the production that first made him fall in love with acting as a timid schoolboy player more than half a century ago - The Happiest Days of Our Lives. sm
Eleventh Hour starts on ITV1 on Thursday at 9pm.