Katy Perry’s Best Moments Undercover

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She's usually hard to miss, whether she's sporting a cupcake bra in the "California Gurls" video or wearing a teal dress with a "boob window" at the Grammys. Yet on rare occasions, Katy Perry goes unnoticed, and has made undercover cameos on TV shows and in other artist's videos.

Here are some of Perry's greatest cameos and undercover hits.

In March 2012 episode of "Raising Hope," Perry appeared as a prison guard, with long red curly hair who apparently was not familiar with upper-lip waxing. She landed the role thanks to her good friend Shannon Woodward. At the time, Perry said in a statement, "Shannon Woodward is my best friend. A couple weeks ago, I was home, just toasting up a frozen chicken fillet, when she called me up and asked if I wanted to do something 'fun' for a change and try out a guest role on her TV show. I thought, 'Sure, I have nothing else to do, and I like chillin' with my best friend.'"

Back in February 2011, Perry appeared on "How I Met Your Mother," but wasn't exactly undercover. Her appearance as Honey, "the hot cousin of Zoey" was heavily promoted.

Perry's cameos haven't been limited to sitcoms. She's also done soaps. Way back in 2008, when "I Kissed a Girl" was riding high on the charts, she appeared on an episode of "The Young and The Restless" as -- get this -- herself.

Also in 2008, Perry appeared in ABC Family's "Wildlife" in the episode "Life's Too Short," singing on stage.

Bonnie McKee has written some of Perry's greatest hits -- "Teenage Dream," "California Girls," and "Firework" -- so she was undoubtedly down to return the favor by making a cameo in McKee's video for "American Girl" back in June. Yet Perry wasn't the only star turning up. The clip also included cameos by Adam Lambert, Ke$ha, Carly Rae Jepsen, Jason Derulo, Mackelmore, "Glee" star Jane Lynch, and Motley Crue drummer Tommy Lee -- in drag.

Of course, that wasn't the first of Perry's music video cameos. She's in P.O.D.'s 2006 video "Goodbye For Now," providing backing vocals at the end of the clip.

She also appeared in the 2006 clip for the Gym Class Heroes' "Cupid's Chokehold"/"Breakfast in America" with her then-boyfriend Travis McCoy. She's not the only one making a guest appearance in the clip, either. It also features Fall Out Boy's Patrick Stump, who sings the chorus from the Supertramp hit.

And then, she was all over Carbon Leaf's "Learn to Fly" clip back in 2006.

However, not all of Perry's cameos have actually been officially released or broadcast.

Back in 2010, she was cut from then-husband Russell Brand's film Get Him to the Greek. The one-time lovebirds were featured kissing, but it never made the big-screen. "It seemed too much of a literal movie then, which I totally understand from a director's perspective or from a moviegoer's [perspective]," she told MTV News at the time. "If you saw me and Russell making out, although it'd be cute to, 'cause that was the first moment we met, [it would feel like,] 'There's Russell Brand in the movie,' not Aldous Snow, and they want it to be Aldous Snow, [so it's] completely understandable." She did, however, accompany him to the film's premiere.

And then, of course, there was that time back in 2010 when Perry sang "Hot N Cold" with Elmo and it was too hot -- at least for "Sesame Street." When the clip of Perry, wearing a revealing low-cut dress hit the web, parents started complaining. Some of the complaints included: "You can practically see her t*ts. That's some wonderful children's programming," "they're gonna have to rename it 'Cleavage Avenue,'" and "my kid wants milk now." Following the complaints, "Sesame Street" issued a statement that read, in part, "In light of the feedback we've received on the Katy Perry music video which was released on YouTube only, we have decided we will not air the segment on the television broadcast of 'Sesame Street,' which is aimed at preschoolers."

As long as you're not in preschool, we encourage you to check out the clip below.

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