“American Masters” (8 p.m., PBS) opens its 17th season with “Willie Nelson: Still is Still Moving,” an affectionate look at the singer, songwriter and actor whose appeal crosses musical and generational boundaries. “Still” follows Nelson and his remarkably close-knit band and crew as they go out “on the road again” to play at concert halls and honky tonks from Texas to Manhattan.

Much like a Willie Nelson ballad, “Still” has a spare and meandering quality that defies easy categorization. While most biographical documentaries present their subject’s life story in a linear fashion, “Still” lets the story unfold through seemingly haphazard conversations with Nelson and his confederates, including the late Waylon Jennings, Kinky Friedman, Lyle Lovett, Ray Charles and Nelson’s sister Bobbie, who plays piano in his band. Given complete access to Nelson and his entourage, “Still” offers a portrait of a man who has seamlessly integrated his private life and professional image. After decades of touring and a song catalog that includes more than 2,000 songs and 250 albums, Nelson brushes off the idea of retirement. “All I do is play music and golf,” says Nelson. “What do you want me to give up?”

“Great Performances” (7 p.m., PBS) enters its 30th season with “Making ‘The Misfits”‘ a fascinating glance at the doomed collaboration of playwright and screenwriter Arthur Miller, Marilyn Monroe, John Huston and Clark Gable as they attempted to make “the ultimate motion picture.”

“The Misfits,” was released in 1961 to mixed reviews. Gable, then 59, insisted on doing his own stunts in the Nevada heat and died soon after its completion. Monroe and Miller’s fabled marriage also withered in the desert, as Monroe romanced French actor Yves Montand and Miller developed a relationship with Inge Morath, a photographer who documented the making of “The Misfits.”

More popular than ever, “Law & Order” (9 p.m., NBC) enters its 13th season with a tale about homicidal religious zeal. Retiring U.S. Sen. Fred Thompson joins the cast as Dist. Atty. Arthur Branch. No stranger to the camera, Thompson appeared in many movies and TV films, including “The Hunt for Red October,” before entering the Senate as a Republican from Tennessee in 1994. Thompson was briefly considered a potential 2000 presidential candidate. While many, including President Reagan, have migrated from show business to politics, Thompson may be the first star-turned-statesman to return to his actor’s mark. He’s certainly the first sitting senator with a steady gig on a TV drama.

Tonight’s other highlights

Scheduled on “60 Minutes II” (7 p.m., CBS): America’s love affair with the mob; on tour with the Rolling Stones.

Major League baseball playoffs (7 p.m., Fox).

Jack Osbourne (“The Osbournes”) guest stars on a two-hour season sixth-season premiere of “Dawson’s Creek” (7 p.m., WB).

George searches for his biological father on the second season premiere of “George Lopez” (7:30 p.m., ABC).

Twelve couples gather in the Florida Everglades to compete on the globe-trotting game show “Amazing Race 3” (8 p.m., CBS).

Bartlet assembles a team to face an international legal challenge on “The West Wing” (8 p.m., NBC).

A young girl (Mae Whitman, “State of Grace”) requests a radical procedure on “Presidio Med” (9 p.m., CBS).

Kellerman procures a heart machine to save a dying patient on “MDs” (9 p.m., ABC).

Kevin Flynn hosts “Ultimate Collectors” (9 p.m., HGTV) a celebration of pack rats, including a Tennessee man with more than 1200 Donald Duck artifacts and a Texas woman whose home is a shrine to the Dallas Cowboys.