The hotel heiress guests on the Oct. 8 episode of Supernatural as a demon who feeds on the disorienting power of celebrity.
The former Buffy star plays a Mord-Sith named Triana in the season-two premiere of Legend of the Seeker, airing Nov. 7 in syndication.
The CW gets a little synergy going when the Top Model host appears as herself on Gossip Girl.
The Broadway baby and former Pushing Daisies star comes to Glee beginning in episode five, airing Sept. 30. Her character, April Rhodes, plays an alcoholic vocal coach who stirs up the glee club kids.
The Disney doll appears on Gossip Girl this season as Olivia Burke, a movie star who falls in love with Penn Badgley's Dan Humphrey.
The celebrity scion continues her tour of every series that will have her. She joins 90210 this season as a lesbian high schooler named Gia who works at the Blaze with Navid and Adrianna.
Bruce and Demi's daughter appeared on The Secret Life of the American Teenager as Heather, a pregnant teenager with an eye for Ben (Kenny Baumann).
What? Reality shows can have stuntcasting, too. Mrs. Tom Cruise appeared on the 100th episode of So You Think You Can Dance to support the Dizzy Feet Foundation.
The country songbird guested on CSI as a doomed young woman who lived at a motel.
The Olsen twin who still acts joined Christina Applegate's sitcom Samantha Who? for a one-ep stint as unredeemable bad girl Natalie.
The reality star played herself in the second-season finale of Greek. She appeared in a dream to Spencer Grammer's Casey Cartwright and offered spiritual guidance.
On Army Wives, Rumer played a wounded soldier's young wife. Her character was befriended by kindly nurse Denise (Catherine Bell). What can we say? We're obsessed with Rumer's impressive and slightly frightening ambition and ancillary work ethic.
Oh look, it's L.C.! Again! The Hills star played herself at a party attended by the Privileged twins, Rose and Sage (Ashley Newbrough).
We love you, Liz Lemon (Tina Fey), but shut up. Borpo is talking.
Fashion designer and onetime reality star Nicole Richie and her onscreen hubby, Ben Savage, both kicked ass when they dropped by Chuck to remind Sarah Walker (Yvonne Strahovski) of the torments of high school.
The erstwhile Joey did a favor for her old Dawson's Creek show runner, Greg Berlanti, and appeared on his ratings-challenged ABC drama, Eli Stone. (She even did a little dream-sequence song-and-dance number.)
It didn't turn out so well in the end, but when LiLo first landed a gig on Ugly Betty as mean girl Kimmie Keegan, everyone thought the wayward actress had finally gotten a real job.
The pop diva's appearance on HIMYM was not the debacle everyone expected. She was cute, the storyline was great, and later she hooked up with Neil Patrick Harris. Everybody wins.
The former Spice Girl and the celebrated designer guest-starred in Ugly Betty's "A Very Posh Wedding" episode, wherein Wilhelmina (Vanessa Williams) tried to seal the deal with tycoon Bradford Meade (Alan Dale).
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