Over the years, reality TV shows have made countless celebrities out of regular people doing regular everyday things, with a spice of drama sprinkled into the final product. While this genre has provided a vehicle for fame for "regular people," these shows have also featured cameos by celebrities, whether it’s to introduce something, promote a project, or even participate in a bigger way that goes beyond a traditional fleeting moment.

The celebrity cameos on reality TV shows run the gamut, from dating shows to competition shows, and more. The best ones stand out for numerous reasons, often because the celebrities came as a surprise. In each instance, they added something interesting to the mix or came completely out of left field.

10 Lance Bass

'The Circle,' Season 2

In the second season of The Circle, Lisa Delcampo came into the game pretending to be former NSYNC boy band member Lance Bass. She chose him for good reason: she has worked as his personal assistant for years and knows him inside and out. She was confident she could fool others into thinking she was the real Bass, and maybe even be a starstruck player or two. With most players being in their 20s, however, only a handful of them even registered who he was.

Bass himself didn’t appear live on the show, but he did send a video message wishing Delcampo luck that was aired on the show. It demonstrates that he’s a good sport for agreeing to let Delcampo go on the show pretending to be him and supporting her throughout the journey. For kids who grew up in the ‘90s, it was a welcome cameo.

The Circle can be streamed on Netflix in the U.S.

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9 Mel B and Emma Bunton

'The Circle,' Season 4

A second entry from The Circle, Mel B and Emma Bunton from The Spice Girls technically had more than just a cameo. They actually played the game for the first five days, living together in an apartment just like the other competitors. They hid their identities, though, playfully pretending to be a 28-year-old children’s author named Jared.

Before they left, the other houseguests were told that two Spice Girls were among them and the others spent much of their conversations trying to figure out which player they were catfishing as. It was hilarious to see two mega pop stars let their guards down and play the game just like the others. They were never in it to win it, just as part of a twist, and revealed to the other houseguests in a short video cameo that was played back to them. The fact the pair took the game seriously made the appearance so much better.

The Circle can be streamed on Netflix in the U.S.

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8 Joel McHale

'RuPaul's Drag Race,' Season 11

Actor and television host Joel McHale popped up on an episode of RuPaul’s Drag Race, one of the best reality competition shows of all time, to surprise all the queens there. He served as a judge and brought his signature loud and hyper comedic style to the challenge.

His hilarious banter with regular judge Michelle Visage, who was visibly annoyed by his judging style, made the episode especially hilarious and memorable. While McHale's rowdy judging style wasn't for everyone, and marked a departure from the usual on the show, that's precisely what made the cameo so funny, and his cameo has become one of the most famous, and talked-about, appearances in the history of Drag Race.

7 Bob Dylan

'Pawn Stars,' Season 3

Way back in 2010, the famously reclusive musician Bob Dylan made an unexpected cameo on the reality show Pawn Stars, which features the daily business happenings at the World Famous Gold & Silver Pawn Shop in Las Vegas, a family-run business that runs round the 'clock and has been open since 1989. Given the nature of the business and the hours it's open, it's no surprise that the owners meet some interesting characters offering unique goods, some of which can be worth tons of money. In this episode, a man sells a Bob Dylan vinyl to the shop for $50, and the owner, Rick Harrison believes that he can increase the value exponentially for resale if they can pull off the seemingly impossible thing: getting it signed by Dylan himself.

He sends the less-than-intelligent Chumlee to get the job done, and he succeeds in tracking down the artist, who happens to be in town for a concert. Hilariously, Dylan is completely taken aback when he runs into a strange man holding his album (not to mention being followed by a camera crew). But Chumlee ruins the plan when he tells Dylan to get the autograph out with his own name. Considering the record could have been worth thousands, it was one of Chumlee's many blunders on the show, but a fabulous get to capture Dylan on camera for the show.

Pawn Stars can be streamed on Hulu in the U.S.

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6 Machine Gun Kelly

'Catfish,' Season 4

This was technically more than a fleeting cameo, since Machine Gun Kelly appeared for the entire episode of Catfish as a guest host alongside host Nev Schulman. But it’s worth including it on the list because it was so memorable. Schulman is known for inviting different celebrities to help him with investigations when his regular co-host Kamie Crawford isn’t there. But this situation turned out to be one of the most shocking. Hundra, it turned out, was using the show to help her come out to her parents, afraid of revealing to them that she was gay. It was all an elaborate scheme to get on television by all parties involved.

Seeing MGK go along for the ride with Schulman and understanding how many twists and turns the show can take was entertaining. He fully immersed himself in the experience, and even got caught up in the drama, upset at how the ladies had played them like fiddles.

5 Kevin Jonas - 'The Real Housewives of New Jersey'

'The Real Housewives of New Jersey,' Season 6

Kevin Jonas made a cameo in The Real Housewives of New Jersey as a contractor leading the construction of Kathy Wakile’s house. It wasn’t all fiction, though. Jonas, who hails from New Jersey, does indeed own a construction company. In the cameo, Wakile’s sister Rosie goes to the property to check it out with her sister and says to Jonas “don’t you sing or something?” He replies, “that was my day job. Now I’m doing this.” He wasn’t joking either. It was his company that purportedly handled the job, according to AOL.

He also, with his company, built a house for his own family. The cameo, it seems, was an ask for a show rooted in truth, and Jonas happily agreed to go on screen for it. The jokes continued when Rosie asked if they might find N’SYNC as their landscaper next. Even more interesting is that Jonas’ wife Danielle had been offered a spot on the show and turned it down, according to Today.

4 David Spade

'Bachelor in Paradise,' Season 7

Following backlash against The Bachelor host Chris Harrison, The Bachelor in Paradise went ahead as planned, but with a series of guest hosts to help tie the show together. The list included names like Lance Bass, Lil Jon, and Tituss Burgess. But one of the most surprising guest hosts was David Spade, who showed up for more than a short cameo, but ended up overseeing multiple episodes. A long-time fan of The Bachelor, Spade has memorably parodied the show in his comedy. When creator Mike Fleiss reached out to ask him to guest host, according to Variety, Spade felt like he just had to say yes.

Spade says he chose Bachelor in Paradise because it’s less serious than the more intense main show. He was his usual comedic self, never holding back with his biting commentary. He was so popular because not only is Spade incredibly funny, but since he has been watching the show for years, he knows all the people, the backstories, and how the show itself works. This wasn’t a matter of an actor reading lines from a teleprompter: Spade got totally involved in the experience.

(IT)

Bachelor in Paradise can be streamed on Hulu in the U.S.

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3 Post Malone

'Ghost Adventures,' Season 17

No one could have expected to see Post Malone show up in Ghost Adventures, one of the best paranormal shows. But he was a fan, and when the crew traveled to Arizona to investigate a location known eerily as The Slaughter House, he joined them. The creepy venue was a meatpacking plant but has been turned into a haunted attraction where people believe ghosts exist and haunt them.

Malone fully involves himself in the paranormal activity, including while Zak starts to feel a dark energy. Fans loved seeing Malone get so worked out, becoming terrified at the happenings as the group began to explore and sense presences. Malone followed other musicians who had previously made a cameo appearance in Ghost Adventures, including Vince Neil from Motley Crue and country music star Loretta Lynn.

2 Dr. Drew

'Jersey Shore Family Vacation,' Season 4

The friends were at their wits’ end with a lingering feud between Angelina Pivernack and Jenni Farley. It was causing friction in the house and making planning the next vacation near impossible. So, their friends decided to take drastic measures. They called Dr. Drew Pinsky to sit down with the two women and try to help resolve the situation.

Pinsky, of course, rose to fame with his radio talk show Loveline, then later his many TV shows and podcasts. Hilariously, Pinsky didn’t know what he was in for, and had a tough time getting through to the two women. His short segment on the show helped the messy situation, at least getting the two women in the same room together. It was an unexpected cameo, but it made total sense given the situation.

1 Billy Eichner

'The Bachelor,' Season 23

Billy Eichner memorably appeared on The Bachelor, one of the best network reality TV shows. He made a joke about Colton Underwood being the first gay bachelor. As it turns out, Underwood later officially came out as gay. Eichner told US Weekly he didn’t actually believe Underwood was gay at the time he made the comment on the show and expressed his happiness for the former competitor for living his truth.

That moment aside, Eichner’s cameo was hilarious. He appeared as a camp counsellor while the cast was on a group date. The ladies looked completely confused at his presence. Eichner had a one-on-one conversation with Underwood where he talked about Underwood’s lack of experience in the bedroom, and was generally his usual goofy and sarcastically funny self.

The Bachelor can be streamed on Hulu in the U.S.

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