"You all know the reasons which have impelled me to renounce the throne. . . . "

The stiff figure speaks to the mikes, fingers interlaced before him on the table, his face composed but not relaxed: an act of will.

". . . But you must believe me when I tell you that I have found it impossible to carry the heavy burden of responsibility and to discharge my duties as king as I would wish to do without the help and support of the woman I love."

The voice, steady but high with tension, is exactly how we remembered it from the records and newsreels and maybe even firsthand, from the radio in 1936 when Edward VIII of Great Britain abdicated so that he might marry Wallis Simpson.

It is not the duke of Windsor, of course. It is Edward Fox, the English actor remembered especially for "The Go-Between" and "The Day of the Jackal" and for his remarkable Gen. Sir Brian Horrocks in "A Bridge Too Far."

Fox and the American actress Cynthia Harris will play the leads in "Edward & Mrs. Simpson," a meticulously documented TV series premiering tonight on Channel 5. The first segment of 90 minutes will begin at 7:30 p.m. The other five hour-long shows air at 8.

"I'm not a method actor," Fox protested politely during a quick visit here.

"He is! He is!" cried Cynthis Harris, who then explained to him that all it meant was that he had logged dozens of hours studying every move of Windsor's ever recorded on film, listening to The Speech a hundred times, grilling old friends and servants to get just exactly the way the Duke walked, listened, laughed, lit a cigarette. . . .

Not only did Lady Frances Donaldson, author of "Edward VIII," on which the series is based, stay close to the set during the seven months of filming, but people who knew the Windsors in the years up to the abdication came around to give advice. They ranged from equerries to Lady Diana Cooper.

And great chunks of the picture were made on 30 locations, from Kenya to a South Wales coal mine to the King's favorite royal residence, Fort Belvedere, now owned by an Arab. As usual with British TV, the efforts at realism were just short of maniacal, with the interiors of Buckingham Palace and post Quaglino's restaurant and other haunts reproduced down to the very wallpaper.

"It wouldn't do to pick up a 1978 lighter when you were supposed to be in a 1930s drawing room," said Harris. "This is life viewed as the '30s viewed it, not a '70s comment on it." She laughed. "I wondered who that little gray man was who followed me around for seven months. Then I realized he was guarding the rubies. Which kept falling off."

Most of the time she was decked out in $150,000 worth of jewels resembling treasures given Wallis by Edward, loaned for the occasion.

Costume and set design, by the way, won awards when the series aired in Britain, as did Fox's acting.

"It's easy, the external part," he said. "You pick up the gestures and the voice and the rest of it. But the inner sense is something else."

The part didn't exactly come naturally for the 40-year-old Fox, for though he looks superficially like Edward VIII, his face is stronger and he certainly doesn't have that famous haunted expression, the expression of a small boy who has just gone to the bathroom in his pants.

And if Fox did go to Harrow and serve in the Coldstream Guards, he also worked in a department store and was fired for wearing a checked suit. He insisted his part was better written than the Simpson part.

For that matter, it couldn't have been easy for Harris either. On the set, when she took off the makeup that his her freckles and shook her hair loose from the severe Simpson coiffure, stagehands literally didn't recognize her and she had to introduce herself.

As the Duchess she is brittle and self-conscious, forever trying to keep those large, capable hands from sight, always dressed too perfectly. It takes an effort to visualize this formal personage in the easygoing California spontaneity of Cynthia Harris . . . whose hands are not large at all.

"The thing is," Fox pointed out, "we're both trained on the stage."

Harris in fact was starting a new play, a remake of "Mary, Mary," when an agent told her she absolutely must do Willis Simpson. Asked to read something Thirties-ish for the screen test, she wrote a monologue herself and won the part instantly.

"I was so worried about working with Edward Fox.I couldn't think what I'd seen him in. And then someone said he was General Horrocks -- the only good thing about that terrible long boring war movie -- and I knew it was going to be all right."

As actors accustomed to the peculiar requirements of both stage and film, both of them found TV no particular problem, since production values in topflight British television rival those of the major film studios.

There was, of course, the business of the script, which kept changing from day to day as new material was added -- the Windsor story being a live news item these days.

"We didn't begin with half the authority we had at the end," Harris said. "We met more and more people who knew them and could give us new knowledge of them."

And Fox, asked about Edward's brush with Hitler (who at one point hoped to make him puppet king of a defeated England), noted that Edward "was extremely naive, not politically astute at all." He found it helpful, yet also more difficult, that Edward was an historical person with depths and intricacies far beyond any imaginary character.

"We didn't fall into the relationship of Edward and Wallis, but we did find that we got on very well. Because they were so close."

"Never a cross word between us," Harris added.

She and Fox feel that their long study of Edward and Mrs. Simpson has given them insights into those over-exposed personalities. Edward may have been dominated by the Duchess, may even have sought that domination, but she needed him too, Harris said.

"He could handle crowds, you see, he was used to public life and speeches, and she was quite shy about it. When she had to make some public appearance she'd look to him for encouragement, and he'd give a little nod, a wave, and it gave her confidence."

The Windsor affair, called a political thriller and the love story of the century, is more than anything a study of the British system, its society, its attitudes to life and love and royalty. Where else in the world could a king's proposal of marriage all but topple a government?