Alan Tudyk

Alan Tudyk

A former star of "Firefly," an animated version of Lauren Conrad and Motley Crue are among the guest stars livening up the FOX schedule at the end of the season.

The network's May sweeps lineup boasts the usual heavy complement of guest stars, including the previously announced Leonard Nimoy ( "Fringe"), Mekhi Phifer ( "Lie to Me") and the return of Eric Millegan as Zach in the "Bones" season finale. The roster also includes Jodie Foster and Ellen Page on " The Simpsons," "Hills" star Conrad, Drew Barrymore and Neil Patrick Harris on "Family Guy" and several "MadTV" alumni returning for the series finale.

Some highlights:

- Ex-"Firefly" regular Alan Tudyk will guest on "Dollhouse" Friday, May 1, playing the "agoraphobic designer of the Dollhouse," who comes into the picture in the course of Ballard's (Tahmoh Penikett) investigation.

- The "Bones" finale on Thursday, May 14 will feature several guest stars for an episode that features the regular cast "tak[ing] on various roles outside their normal duties, including serving as nightclub staff [where a murder takes place] as well as local law enforcement." The episode will also feature the return of Millegan's Zach, Brendan Fehr as Booth's ( David Boreanaz) brother -- he also appears in the April 30 episode -- and Motley Crue.

- "Juno" star Page will play a teen pop star named Alaska Nebraska in the May 3 episode of "The Simpsons," whom Lisa claims to be friends with when she's sent to a new school. Foster will provide the voice of a grown-up Maggie on May 10, when the Simpson women tell stories of some great women in history and literature.

- Barrymore, Conrad, fellow "Hills" star Audrina Patridge and late-night hosts Jay Leno, Jimmy Fallon and Craig Ferguson will all guest on "Family Guy" May 3, in an episode where Conrad helps Brian get over the news that his ex (Barrymore) is getting married. Harris and his "How I Met Your Mother" castmates Josh Radnor and Jason Segel appear the following week.

- The series finale of "MadTV" on Saturday, May 16 will include the return of former cast members Will Sasso, Alex Borstein, Mo Collins and Debra Wilson Skelton, along with a guest appearance by Fred Willard.