"TV movies have become an area to pose a problem and then solve it," he said. "I'd rather let the movie be a journey and let the viewer think about it at the end."

Hank's domineering mother is played effectively, if all too briefly, by Allyn Ann McLerie. Clu Gulager is fine as Junior's laid-back, wealthy friend, J. R. Smith.

The movie is based on the book "Living Proof" by Hank Williams Jr. and Michael Bane and directed with a bit of gritty a realism by Dick Lowry.

"The autobiography was brought to me by my partner, Michael Lepiner, with the idea that I would co-produce and act," said Thomas. "I was doing an apprenticeship as a producer, and it felt good. There's total involvement, particularly when you're acting in the picture. There's something about having creative control and then going before the camera to make it happen."

Thomas had a bit of homework to do before stepping in front of the camera. He does his own singing early in the show, when Junior is still performing Senior's music.

"Then we used Hank's voice in his transitional phase," said Thomas. "It was terrifying to carry so much of the movie musically. I didn't play guitar and country music is not my area. I took guitar lessons and was surrounded by solid musicians and just faked 'em out!"

Whether Thomas fakes 'em out dramatically, in look and style, as well as musically is a serious question, and a close call. Thomas' looks haven't changed much in recent years, and it isn't until the end of the show, when he affects a full beard, sunglasses and a Western hat that he becomes someone else entirely.

"Time," said Thomas. "It takes time. You can't obliterate an image like that. You have to balance the scales. You do that by developing a body of work, and that takes time."

His next stop will be the stage, with a spring stint planned with the Circle Repertory company in New York. Before that, there'll be time with his wife, 6 1/2-year-old son and triplets. "The family's great," he said. "They're growing like bread dough."

Richard Thomas is asking a lot of his television audience this week. He's asking viewers to forget all those years he played the elder son, the clean-cut aspiring journalist on "The Waltons," and to accept him as a hard-drinking, womanizing, pill-popping country singer. And after you've seen him in "Living Proof: The Hank Williams Jr. Story," he doesn't want you to say, "Good night, Hank-Boy."

Taking the part of a man he describes as an "outlaw type" certainly has to cast Thomas' image in a different light. "Damn right," said Thomas. "The part appealed to me. It's a challenge, a stretch for me as an actor. That's the fun part.

"But it's not simply being something different. In the course of the film you see Williams move through transition.That's what I was looking forward to."

What viewers can look forward to Monday night (9 on 2 and 4) is two tightly compressed hours in which roughly 30 years of Hank Junior's life is unraveled, starting from the time he was herded on stage by his mother, carrying a guitar bigger than he was, and urged to mimic his late father's greatest hits.

On the surface, the story deals with Junior's struggle for a musical and personal identity separate from his father's. But along the country road to self-discovery, he becomes more like his father, flirting with and succumbing to the temptations of musical road life.

"His relationship with women is important too," said Thomas. "He's unable to carry on an adult relationship with a woman until the end. He kept [falling for] women like his mother."

There is no dramatic conclusion to "Living Proof," no sudden or startling change in Williams' character. "He's still kind of a wild man," Thomas noted.