The new (let’s not call it original) Western “A Gunfighter’s Pledge” (8 p.m. Saturday, Hallmark) contains many familiar plot points of the genre. A lone lawman finds himself besieged by bad guys who’ve just busted out of prison and return for revenge; a good guy stumbles back to home and hearth only to find his loved ones slaughtered; a noble family fights evil swindlers out to steal their sacred land.

“A Gunfighter’s Pledge” hits these notes and many others, and all before the first 20 minutes elapse. But who watches Westerns for the plot?

Star Luke Perry, who always seemed too old for “Beverly Hills, 90210,” doesn’t seem seasoned enough to play the noble lawman dragged back from near-retirement for one last stand.

¢ The documentary series “Lockup” (9 p.m. Saturday, MSNBC) continues its look at the effectiveness of America’s prison system, where the population of incarcerated people has grown to more than 2 million.

¢ Along with the new “Get Smart,” virtually every TV comedy from the 1960s has been turned into a movie. “The Beverly Hillbillies,” “Bewitched” and even “Car 54, Where Are You?” have been recycled. But it’s a safe bet that “Hogan’s Heroes” (running in marathon fashion from 5 a.m. to 2:30 p.m. Sunday, TV Land) will never make it to the big screen.

¢ “Nick News with Linda Ellerbee” (8 p.m. Sunday, Nickelodeon) discusses the pressures on the children of fathers and mothers fighting in Iraq and Afghanistan.

¢ Science launches a week of space programming with “Moon Machines: Saturn V” (8 p.m. Sunday) and “Moon Machines: Command Module” (9 p.m.).

Saturday’s highlights

¢ Yoda educates Luke in the 1980 sequel now titled “Star Wars Episode V: The Empire Strikes Back” (5 p.m., Spike).

¢ Robert Duvall stars in the four-part 1989 miniseries “Lonesome Dove” (6 p.m. and 8 p.m. Saturday and Sunday, ION).

¢ U.S. Olympic swimming trials (7 p.m., NBC).

¢ Lindsay Lohan stars in the 2004 comedy “Confessions of a Teenage Drama Queen” (7 p.m., ABC).

¢ “Yves St. Laurent: 5 Avenue Marceau 75116 Paris” (7:20 p.m., Sundance) profiles the influential designer who died June 1.

¢ Murder attends a medical convention on “Law & Order” (8 p.m., NBC).

¢ Hell hath no fury, and makes no better suspect, than a woman scorned on “Law & Order: Criminal Intent” (9 p.m., NBC).

¢ Exit, pursued by a dragon, on “Eli Stone” (9 p.m., ABC).

¢ Jon Bon Jovi hosts “Saturday Night Live” (10:30 p.m., NBC), featuring musical guest Foo Fighters.

Sunday’s highlights

¢ Scheduled on “60 Minutes” (6 p.m., CBS): the Congo’s endangered gorillas; Douglas Feith and the path to war; the endangered penny.

¢ U.S. Olympic trials (6 p.m., NBC) in swimming and track and field.

¢ Scheduled on “Dateline” (8 p.m., NBC): memorable calls to 911.

¢ Inspector Lewis investigates a suspicious suicide on “Masterpiece” (8 p.m., PBS, check local listings).

¢ Contestants from former VH1 shows compete on “I Love Money” (8 p.m., VH1).

¢ “Design Star” (8 p.m., HGTV) contestants must renovate suites at the Opryland Hotel.

¢ The final five prepare a meal for Rachael Ray on her show on “The Next Food Network Star” (9 p.m., Food).