Larry David on Hannah Montana
Probably the last place you’d ever expect to see “Seinfeld” creator Larry David is hanging out with the still-innocent tween idol Miley Cyrus on the set of her show “Hannah Montana.” You can thank David’s young daughters, who were huge fans of the pop star’s show, for this bizarre cameo in which the funnyman plays himself.
Nicole "Snooki" Polizzi on Supernatural
An MTV staple, you may be used to seeing Snooki all over your TV either running around the Jersey shore in drunken exuberance or, more currently, navigating motherhood. But viewers were thrown off to see the “guidette” appear in the sci-fi drama playing a demon version of herself.
Paris Hilton on Supernatural
Another bizarre cameo from “Supernatural,” Ms. Hilton played a one-episode villain. Paris portrayed a shape-shifting god obsessed with being worshipped — maybe that’s not such a stretch for the attention-seeking celebrity.
Justin Bieber on CSI
Back when he was still a squeaky-clean teen dream, Bieber shocked his fans by playing a serial bomber on the popular crime drama. The baby-faced star wound up actually dying on-screen in the role.
Britney Spears on How I Met Your Mother
Britney Spears could have any man she wants, but during her guest role as the dental receptionist Abby on “How I Met Your Mother,” she shamelessly threw herself at both Ted and Barney. Fans were surprised to see Spears acting in a sitcom, but her performance was so good that she was asked to recur her role in a later episode.
Shakira on Wizards of Waverly Place
Before she was a judge on “The Voice,” Shakira had a very bizarre cameo on Disney Channel’s “Wizards of Waverly Place.” The magical show revealed that Shakira has, in fact, always been the main characters’ uncle shape-shifting into the “Hips Don’t Lie” singer. Shakira also sang a brief duet with Selena Gomez in the episode.
James Franco on General Hospital
While Franco first made his name on television, his decision to join the soap opera “General Hospital” in 2009 was bizarre even for the left-field actor. Playing an artist/serial killer with his same name, Franco further confused audiences by calling the unremarkable role “performance art.”
Buzz Aldrin on 30 Rock
The famed astronaut appeared as a crazier version of himself in Tina Fey’s masterfully manic comedy. The role featured Fey’s character finding out Aldrin could have been her father, and the two share a memorable scene where they yell at the moon.
Michael Jackson on The Simpsons
The “Thriller” singer was a huge fan of “The Simpsons” — so much so that he called the show’s creators and asked to do a guest role. Although he is credited under a pseudonym, Jackson provided the voice for mental patient Leon Kampowsky, who has delusions that he is Michael Jackson.
Kathy Griffin on Law & Order: SVU
The famous comedian got uncharacteristically serious for her guest role as a lesbian activist named Babs Duffy on “Law & Order: SVU.” Viewers were shocked to see Griffin portraying a serious role, and she even shares a kiss with Mariska Hargitay in a “behind the scenes” video.
Ashlee Simpson on 7th Heaven
Before releasing her first album, Jessica’s punky little sis was a recurring character on the preachy drama. Playing Simon’s girlfriend Cecilia for two seasons, this is Simpson’s longest role to date, as she went on to be much more focused on a music career.
Charlize Theron on Arrested Development
While Theron is a staple on the big screen, she is a very rare sight on television. That is why “Arrested Development” fans were surprised to see the South African actress in a recurring role on the quirky comedy. Another shocking twist revealed Theron’s character of Rita to be a mentally challenged woman, although she doesn’t appear to be at first.
Brad Pitt on Friends
Like Theron, Pitt was rarely seen on television after he became a mega star. But in 2001, when he was married to Jennifer Aniston, he made an appearance on “Friends.” Pitt played a victim of Rachel Green’s (Aniston) high school bullying who is continually hostile towards her.