Crowning achievement: 'Tudors' star ready to end his reign as Henry VIII

On Showtime's "The Tudors," King Henry VIII is about to find his sixth wife - but time isn't on his side.

The fourth and final season of the hit historical drama hasn't lacked for passion or drama, but its mood is definitely on the autumnal side, as the once-vital Henry (Jonathan Rhys Meyers) goes through his last years wracked with pain, illness and bitterness. In the episode airing Sunday, May 16, he sets his cap for Catherine Parr (Joely Richardson, "Nip/Tuck"), who will become his sixth and final queen in one of Henry's few successful marriages.

As the clock ticks down to Henry's death at age 55 (four episodes remain after this Sunday's), his real-life alter ego took some time for reflection himself, after having spent more time living with this complicated monarch than any other actor in TV or film history. Rhys Meyers isn't an actor who frightens easily - he mutated his Irish brogue into a Southern drawl for a startlingly convincing turn as Elvis Presley in a 2005 CBS movie that earned him a Golden Globe Award and an Emmy nomination - but he concedes that he knew he had his work cut out for him almost as soon as he signed on for "The Tudors."

"I started by researching but then realized that would be just a huge amount of frustration, since I didn't remotely look like Henry," says the actor, adding that paintings of Henry often were manipulated for propaganda purposes.

"I would start thinking of Henry as he was in history, not Henry as I was forced to make him. I had to play a very well-known historical figure without physically resembling him. Elvis actually was much easier, because I sort of looked like Elvis.

"I had to get the audience to 'buy' Henry without the physicality. That was much more complicated, so it became more of a boon to just concentrate on (series creator and writer) Michael Hirst's idea of Henry and only see him as I saw myself."

For each of the four seasons, the role of Henry took six months a year out of Rhys Meyers' schedule, presenting a series of technical challenges that shifted with the king's age and historical surroundings. Season four has presented unique rewards and pitfalls, the actor explains.

"Its advantages were that it allowed me to be very free in my performance, because I found it very freeing to have that mask of age," he says. "(Henry) was able to hide a lot more behind it than you might think. I found myself using it as part of my armor. Then again, it's very difficult to work with beards and prosthetics as I had to do as Henry got much older. That meant complicated, 14-hour days, so it was hard work."

He gives Hirst high marks for his creative vision and insists that their working relationship generally went very smoothly, although they did "tussle" occasionally, perhaps most notably over the issue of the role's sexual content. "(Michael) is very daring, whereas the real Henry was rather prudish, but he helped me see the sexual scenes as being about sex as power: the power of one animal over another,"

Rhys Meyers explains. "It was a form of control, not something that was erotic, not 'The Arabian Nights,' but something more sinister. That's how I came to see the sexual side of Henry. Everything was a means to an end."

Including, it seems, those lavish court entertainments Henry threw almost every night of his reign. Those extravagant gatherings weren't just camera-friendly bonuses for the Showtime series, nor were they as congenial as the king's long-ago guests might have imagined as they danced and gossiped.

"Henry was a great people watcher, very astute like that," Rhys Meyers says. "He would invite lots of people, lords and ladies and gentlemen. He liked to keep them at court because he liked to watch what they were doing."

If Henry's final years were spent in a good deal of pain and bitterness, Rhys Meyers says he's feeling serene himself after going through a dark spell that included the death of his mother and reports that the actor was hitting the bottle too much. He's pushed through all that, he insists, and currently is weighing his next career move. And it probably won't include the role of Henry VIII, he suspects.

"It's difficult to say," he says. "Certainly there is more to say about Henry. I think 'The Tudors' is incredibly brilliant, and Michael Hirst and everybody worked very, very hard to make it what it was. But to be honest, I don't think I could (play Henry again)."