TOP CHEF: The "Restaurant Wars" challenge returns to "Top Chef." (David Moir/Bravo )

NBC heralds the holiday season again with a dazzling display of musical talent and the lighting of America’s most famous tree during the 16th annual “Christmas in Rockefeller Center” (NBC at 8 p.m.) telecast. Musical guests Mary J. Blige, Toni Braxton, Mariah Carey, Kelly Clarkson, Ariana Grande and more perform current hits and holiday classics.

Framed as an investigation into popular culture’s obsession with beauty, “Revealing: Face Value” (Sundance at 9) explores the allure of looking good through interviews and social experiments. Someone is offered a free beauty treatment with the promise of youth, although the person knows the product has awful side effects. Hosted by Elle’s creative director, Joe Zee, the special affirms the perceptions that it’s not just women who are weighed down by society’s pressure to be perfect and that a whole new market is just starting to boom.

Cam’s ruthlessly competitive side is exposed as a big football game approaches on “Modern Family” (ABC at 9). Elsewhere, Claire wants to prove herself at work, and Phil takes it upon himself to teach his children about optimism.

“Top Chef” (Bravo at 10) brings back the iconic “Restaurant Wars” challenge, in which the chef-testants face the task of creating pop-up restaurants to impress a renowned panel of judges. Restaurateur David Chang is guest judge.

Twenty years after the Dec. 7, 1993, Long Island Railroad mass shooting that left six people dead and 25 wounded, “Terror on a Train” (Investigation Discovery at 10) looks at the tragedy. The documentary is centered on the survivors and the families of the victims, who share their terrifying experiences and how they continue to cope.

Cordelia and the girls band together to stop Fiona on “American Horror Story: Coven” (FX at 10). While she’s still wrapped up in a dangerous relationship, Delphine and Marie put an end to their rivalry for good.

Actor Woody Harrelson and World Series MVP David Ortiz of the Boston Red Sox join “The Late Show With David Letterman” (CBS at 11:35), with musical guests The Wanted.

Actress Melissa McCarthy and television personality Andy Cohen are on “The Tonight Show With Jay Leno” (NBC at 11:35), with a musical performance from Empire of the Sun.

Actor Benedict Cumberbatch comes to “Jimmy Kimmel Live” (ABC at 11:35), along with singer R. Kelly, who stays for an interview and a performance.

—Rachel Lubitz