Mediocre holiday movies can be so instructive. What can we learn from “Secret Santa” (8 p.m. Sunday, NBC)? Well, for one thing, when up against a “Survivor” finale, NBC will slavishly imitate CBS to pick up the ratings scraps. “Secret” has all the earmarks of an Eye Network saccharine-fest. Spunky reporter Rebecca Chandler (Jennie Garth) goes to a picture-postcard Indiana town to expose the Secret Santa, a stranger who bestows life-altering holiday gifts. When there’s no room at the local inn, she even bunks at an old-folks home — a CBS touch if ever there was one.

Along the way, a second truth emerges: Jennie Garth is dreadfully miscast as an investigative journalist. Her “feisty” acting range runs the gamut from Trista Rehn to Leeza Gibbons.

The third and most interesting thing we learn here is that Steven Eckholdt is quickly becoming the Tom Hanks of the small screen. He’s the handsome but not overtly gorgeous everyguy who sweeps women off their feet. Recently seen in the Lifetime Christmas fantasy “Comfort and Joy,” he plays the town’s young widowed millionaire, the man Rebecca suspects of being the undercover philanthropist.

• No matter who leaves with the loot after the “Survivor” (7 p.m. Sunday, CBS) finale, Jon emerges as one of the most detestable contestants ever to play the game. Johnny Fairplay (as he refers to himself) mixed deviousness, laziness and crude misogyny to earn the wrath of just about everybody on Earth. Want to bet he shows up on “The Surreal Life” sometime before 2005? The whole gang of castaways reconvenes for the “Survivor Reunion” (9 p.m.).
• Who will emerge as the “Biography of the Year” (8 p.m. Sunday, A&E)? Stay tuned. If this year’s cast of characters and next year’s crop of presidential candidates seem too dull, there’s always “Bill Clinton: The True Hollywood Story” (7 p.m. Sunday, E!), a glance at the scandals that engulfed the man from Hope. When are we going to get a tabloid look at the present first family? There’s certainly no shortage of material for a “Behind the Bushes” miniseries.
• Christian Slater narrates “Dinosaur Planet” (7 p.m. Sunday, Discovery), a two-hour look at prehistoric life employing computer-generated graphics to recreate creatures from the Cretaceous period.

Tonight’s other highlights

• Bob Barker celebrates his 80th birthday on “The Price is Right Million Dollar Spectacular” (7 p.m., CBS).
• Elijah Wood is host of “Saturday Night Live” (10:30 p.m., NBC), featuring musical guest Jet.

Sunday’s other highlights

• Scheduled on “60 Minutes” (6 p.m., CBS): the West Bank’s controversial wall; Sen. John Edwards; a repeat report on Russian country music artists Bering Strait.
• Patricia Heaton is host of “Christmas in Washington” (7 p.m., TNT), featuring Ashanti, Hootie & the Blowfish, Joss Stone, Kenny Chesney and Renee Fleming.