Gary Busey is a good ol' boy from Goose Creek, Tex., who went to college on a football scholarship. "But when my knees wore out, I transferred my football ego to Theater, playing football and running over at night and putting on tights . . . Ha!" he laughed.

But though he went to Coffeyville Community Junior College, Oklahoma State University and Kansas State in Pittsburg, he never did get the degree.

No matter. Busey went on to earn an Oscar nomination and awards from the National Society of Film Critics and Los Angeles Film Critics for the title role in the "The Buddy Holly Story" in 1978. He appeared in the 1974 TV movie "The Execution of Pvt. Slovik" with Martin Sheen, and in "A Star Is Born" in 1976 with Barbra Streisand, "Straight Time" in 1978 with Dustin Hoffman, starred in "Carny" and "Foolin' Around" in 1980, co-starred with Willie Nelson in "Barbarosa" in 1982, and more recently appeared in "D.C. Cab," "The Bear" (he plays the late Alabama football coach Bear Bryant), director Nicolas Roeg's "Insignificance" and in a recent episode of HBO's suspense anthology series, "The Hitchhiker," with Geraldine Page.

"I love this business," said Busey, "but I didn't know how to handle success." He gained weight -- at one time he carried 240 pounds on his 6' 1" frame -- and he turned to alcohol and drugs. "I had a cocaine problem for a while," Busey said candidly. And while he was trying to get himself straightened out, he said, he got the role of Bart Winninger in Stephen Metcalfe's drama, "Half a Lifetime," airing Sunday on HBO Showcase.

"I weighed 215 then, I weigh 180 now," said Busey, the ex-athlete proud to be back in shape. "I had a 44-inch waist, and now it's 33. You ought to see me now. I'm 42 -- but I look 33."

"Half a Lifetime" is the hour-long story of four men in their mid-30s, friends since high school, who meet together for a weekly poker game. The beer belly Busey carried then bulges inside the slightly small orange T-shirt and jeans he wears as Bart, a high school athlete gone to pot who claims "the muscle's there -- it's just hiding under beer and hoagies."

And though Gary Busey is not stuck in a boring job and a shotgun marriage, he says he identified with his character. "He was frustrated, not knowing if he was the father of his child, not knowing whether he'd ever get off that machine shop job, and I just took all the frustrations I was going through and latched onto them and made them part of Bart."

Chomping on a cigar and horsing around with his three buddies from high school, Bart longs for the glory days of high school football. He'd like to chuck his present life and get away to Vermont.

Working on "Half a Lifetime" was "the hardest work I've ever done on film -- the pressure was on," said Busey. "We rehearsed the thing like a play, taped on the floor the perimeter of the room the story is set in a half-finished basement rec room , and tried to make these characters come to life. We had a week to cram an hour's worth of information into our hearts and souls. We spent a week rehearsing and a week to shoot . . .

"The great thing about the play for me was the writing of it . . . Any actor could pick up the words. . . . I rely on my instinct, but whenever I would rephrase one of Stephen's lines, it would not work. It would be like the guitarist starting on one beat and the drummer starting on the second."

Having kicked alcohol and cocaine and lost weight, Busey says "things are going fantastic." He's finished a movie called "Let's Get Harry" with Robert Duvall and Mark Harmon about "four plumbers in Illinois who have a friend and brother who's kidnapped by cocaine terrorists in Bogota, Colombia. The State Department won't interfere, so they decide to go get him themselves." He plays an ex-Marine who masterminds the rescue. He's also made "Eye of the Tiger," which he calls "a great picture," playing "a Vietnam vet sent to prison in a frame job and comes back to his wife and daughter, who's 8, and lives in a small town on the Texas-Mexico border . . . It's like 'High Noon' and 'Walking Tall' -- we're making it human, like a Steve McQueen movie, not like Schwarzenegger or Rambo. He stands up for his principles."

Gary Busey (left), Keith Carradine, Nick Mancuso and Saul Rubinek as long-time friends in HBO's "Half a Lifetime."