Celebrity guest stars are always a lot of fun for viewers. Regardless of if they are completely random, surprisingly fitting for the role, or if they have any actual acting talent, guest stars show a heightened engagement with current discourse, including popular or trending figures to ground their product more sternly in current times and get viewers excited in the process.

Whether the guest star is hyped and highly advertised across platforms or a complete surprise to viewers, there is something so exhilarating about seeing a beloved musician in costume. Maybe they’re donning Westerosi armor for a night, playing cupid for a fan favorite slow burn couple, or, just maybe, they’re turning yellow. And of course, any celebrity guest star evokes the age-old question of whether that musician exists in the universe of the series. I mean, do they?

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10Ed Sheeran in ‘Game of Thrones’

In trueEd Sheeranstyle, his guest role as a Lannister solider inGame of Thronesproves that, behind the immense fame and talent, he really is a normal guy. Singing by the fire with his fellow soldiers, the scene shows a rare, tender moment in time when family allegiances and power don’t matter, as Arya Stark sits with the soldiers, and they talk of their “endless adventures” and share food from their hunt.

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In hisinterview on Armchair Expert, Ed Sheeran explained that his guest role was intended as a surprise forMaisie Williams. He said, “I don’t think they had written the ending yet. It was meant to be her last season, but it wasn’t. And as a surprise for her…they would get me on. So, she was meant to turn up on set, and I was by the fire. She was meant to know her lines and everything, get down and be like, ‘Hang on.'"

9The Ramones in ‘The Simpsons’

The Simpsonshas had its fair share of era-defining musical guest stars. ButThe Ramones’ cameo was one of the greatest. Starring in one of the show’s most beloved episodes, a season 5 episode titled “Rosebud,” The Ramones appear as themselves, hired by Smithers to performing at Mr Burns' birthday party and hopefully cheer up the billionaire after missing his childhood teddy bear, Bobo.

In a nod to the band’s success, Smithers introduces them as “fine young men who…are gonna go far,” followed by characteristically punk responses from the band members who shout “this gig sucks” and “up yours, Springfield.”

The Ramones in ‘The Simpsons’

8Pete Wentz in ‘One Tree Hill’

Pete Wentz' guest starring role inOne Tree Hillwas a testament to the show’s willingness to have some fun with the drama and absurdity of the teen genre. The show created a storyline in which fans were supposed to believe an adult Pete Wentz would fall for a teenage girl from a small town in North Carolina. And they did.

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Pete Wentz on One Tree Hill

This cameo was single-handedly responsible for a generation of Peyton Sawyer (Hilarie Burton) wannabes believing they too could pull an emo heartthrob. Whilst his acting was questionable at best, his commitment to the bit was undeniable, showing up to Peyton’s house in limousines, going on weekend trips with her drama-filled friend group and even doing his eyeliner with the girls. He really was the epitome of a Snuffleupagus.

7Prince in ‘New Girl’

PutPrincein anything, and he is going to steal the show. Prince’s appearance inNew Girlwas not only iconic, but incredibly important to the plot. Following Nick’s awkward declaration of love to Jess, which she characteristically responds to with finger guns, Prince’s role came at a time when damage control was in dire need for the couple.

With a glamorous makeover and a chat over some pancakes, Prince helped Jessica Day (Zooey Deschanel) find the confidence to tell Nick she loved him.Jake Johnson, who played Nick Miller in the show, recalledin an interviewthat the pair getting together was crucial to Prince starring on the show, saying “he said he’ll do the show if he can help Nick and Jess get together, and he got to live a little fantasy.”

Prince New Girl 2x1

6Britney Spears in ‘How I Met Your Mother’

WhilstBritney Spears' cameo inGleewas nothing short of life changing, it is her guest role inHow I Met Your Motherthat made both her and the show even more lovable. Starring as Abby the receptionist at the tattoo removal clinic Ted’s visiting, Spears showcases her comedic acting chops through some great one-liners, and some serious (and all too relatable) pining over Ted Mosby (Josh Radnor).

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Britney Spears on How I Met Your Mother

Abby’s character was a masterclass in how to effortlessly embarrass Ted, making fun of Ted’s screams and exposing him for reading a book his crush didn’t like. And who could forget her most painfully relatable line, “when people yell at me, I have a tendency to start crying.” Put Britney Spears in everything.

5Stevie Nicks in ‘American Horror Story’

It’s not too often that fans ofAmerican Horror Storycome together to share in how relatable a scene or a character from the show was. After all, it’s not many people’s dream to be affiliated with Ryan Murphy’s morally grey, and at times psychopathic array of characters. Yet,Misty Day’s reaction to meetingStevie Nicksis a moment music lovers will surely understand, knowing that they too would faint if they came face to face with the rock icon.

In true Stevie Nicks fashion, and as queen of the whimsigoth aesthetic, Nicks appeared in the show’sCovenseason, starring as a witch herself, who performs Fleetwood Mac’s “Seven Wonders” to Misty and her coven of witches. Not only does Nicks' musical persona work perfectly with the season’s focus, but her song choice is highly relevant to the plot, singing as the witches prepare for an exam in which they have to navigate the seven wonders to determine who will be Supreme Witch.

4Taylor Swift in ‘New Girl’

Where some cameos are highly advertised to rally up viewer excitement, theTaylor Swiftcameo inNew Girlwas a complete shock. The singer came into the show at a pivotal point for fans, who were watching with fingers and toes crossed, hoping that Cece wouldn’t go through with her arranged marriage to Shivrang.

Throw in a badger on the loose in the air vents, a bit of eye communication and a horse gone wild, and you’ve gotNew Girlchaos at its best. While fans knew the wedding would never run smoothly - with Cece having no choice but realize her feelings for Schmidt - it was comforting to know that when Elaine (Swift) professed her loved for Shivrang during the ceremony, that at least Shivrang’s feelings would not be hurt.

3One Direction in ‘iCarly’

Nothing says 2012 likeOne Direction(all 5 of them) guest starring on Nickelodeon showiCarly. Before Harry Styles' acting was cause for debate among viewers, his acting was laughably adored by fans, who envied Carly (Miranda Cosgrove) for being able to aid him in his battle with the well known ‘jungle worms’ illness.

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The episode also saw the rest of the band educated on Cat’s infamous “butter sock.” The iCarly gang even showed their love for British culture by making them “British sandwiches” (otherwise known as normal sandwiches).

2Carole King in ‘Gilmore Girls’

Fans ofGilmore Girlswill be aware ofCarole King’s mark on the show, knowing her for her vocals in the show’s theme song “Where You Lead,” and likely singing along with her at the start of each episode. But many fans will likely be surprised to learn that King also plays a well known character in the show, starring as one of the show’s lovable townies.

King stars as Sophie Bloom, the owner of Lane Kim’s favorite store, Sophie’s Music, in Stars Hollow. Sophie plays a big part in Lane’s music career, with the store serving as the place where Lane first begins practicing the drums and buying her own drum kit. She and her band Hep Alien also work at the store in exchange for using it as a rehearsal space (because Lane’s house was never an option, under the watchful eye of Mrs Kim).

1Jennifer Lopez in ‘Will & Grace’

Jennifer Lopez(also known as JenPez according toMegan Mullally’s character, Karen) cameos as herself in the sixth season ofWill & Grace. Lopez performs at Karen’s wedding to Lyle (which ends after only 20 minutes) after meeting Karen in the bathroom at their Las Vegas hotel.

Noting that they have a very important mutual friend (fan favorite Rosario), Karen convinces Lopez to perform at her wedding, singing “Waiting for Tonight,” with Jack (Sean Hayes) joining her on stage. And Lopez' turn as a guest star onWill & Gracedoesn’t end there, with the star returning to the show in its revival seasons, not as herself, but as herShades of Bluecharacter, Detective Harlee Santos.

NEXT:10 Singers Who Guest-Starred On ‘How I Met Your Mother’