On Buffy the Vampire Slayer (8 p.m., WB), Glory makes her move on Dawn while Buffy is preoccupied with her mother's medical tests. Scientific American Frontiers (8 p.m., PBS, check local times) opens its 11th season with host Alan Alda playing guinea pig for experiments that test brain function. In a two-part 3rd Rock From the Sun (8:30 p.m., NBC), the Solomons meet their parallel universe selves. Maybe those characters are on a show that people actually watch. Frasier hits the heights of pretentiousness when he hires a British butler for the Crane household on Frasier (9 p.m., NBC). Angel and Gunn guard a valuable demonic burial shroud, unaware that anybody who gets close to it goes crazy, on Angel (9 p.m., WB). It's a happy, jolly Thanksgiving -- not! -- as Lily and Rick host a blended family feast on Once & Again (10 p.m., ABC).
In TRL Presents: Backstreet Boys Homecoming (8 p.m., MTV), the larger-than-life lads visit the MTV studio to perform songs from their new release, while fans faint outside in Times Square.
Knicks at Magic (8 p.m., TBS)
Maple Leafs at Rangers (7 p.m., ESPN2)
Rosie O'Donnell (syndicated) Samuel L. Jackson
David Letterman (CBS) Faith Hill
Jay Leno (NBC) Arnold Schwarzenegger, Jeffrey Tambor, Sade
Politically Incorrect (ABC) Sen. Arlen Specter, Dweezil Zappa
Conan O'Brien (NBC) Susan Lucci, Orgy
All times Eastern unless noted.