On air for more than 30 years and still going strong, The Simpsons is the longest-running American sitcom of all time. During the years that the show has been captivating audiences around the world, a vast variety of celebrities have guest-starred, some playing themselves, and some playing other characters that make them a little difficult to recognize.

While it’s easy to remember the big names that have appeared as themselves on The Simpsons, it’s more difficult to remember the stars that played various characters across the many seasons, especially when those characters looked so different from them. Keep reading to see which 15 celebrities we totally forgot had guest-starring roles on The Simpsons. Get ready to go down memory lane and have your memory triggered!

15 Matthew Perry Had One Memorable Line As Ultrahouse

Matthew Perry On The Simpsons
IMDb

You’d be forgiven for missing Matthew Perry’s role on The Simpsons. In ‘Treehouse Of Horror XII’ he briefly plays the role of the villainous Ultrahouse when it’s set to Matthew Perry’s voice. His line isn’t difficult to remember, especially if you’re a Friends fan: “Could I be any more of a house?”

14 Meryl Streep Is Talented Enough To Have Played The 10-Year-Old Jessica Lovejoy

Meryl Streep as Jessica Lovejoy
Star Crush

Meryl Streep is the queen of voices, so you might not have realized that she had a guest role on the show. She played the role of Reverend Lovejoy’s mischievous daughter Jessica, whom Bart falls in love with. In a shocking twist of events, the reverend’s daughter ends up being naughtier than Bart.

13 How Did We Forget That Drew Barrymore Played Krusty's Daughter?!

Drew Barrymore as Sophie
Pinterest

For most of the series, Krusty the Clown is portrayed as a bachelor. But in the episode ‘Insane Clown Poppy’ we find out that he has a daughter named Sophie (who bears a resemblance to him). How could we forget that Sophie was played by the one and only Drew Barrymore?

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12 Mr. Bergstrom Couldn't Have Been Played By Anybody Other Than Dustin Hoffman

Dustin Hoffman as Mr Bergstrom
IMDb

In one of the sweetest roles in Simpsons history, Dustin Hoffman starred as Lisa’s charismatic substitute teacher, Mr. Bergstrom. She develops a small crush on her teacher and becomes attached to him, so it’s heartbreaking that he leaves Springfield at the end of the episode. At least he reminds Lisa of who she is.

11 Cool Girl Alex Whitney Even Kind Of Looks Like Lisa Kudrow

Lisa Kudrow on The SImpsons as Alex
The Simpsons Index Podbean

It looks like Matthew Perry isn’t the only Friends star to appear on The Simpsons. Lisa Kudrow, who played Phoebe Buffay, starred in the episode ‘Lard of the Dance’ as Lisa’s cool friend Alex Whitney who is in a huge hurry to grow up. Kudrow nails the pre-teen popular voice perfectly.

10 Reese Witherspoon Played Bart's Other Love Interest, Greta Wolfcastle

Reese Witherspoon As Greta Wolfcastle
Taringa.net

Reese Witherspoon is another famous actor to have starred as a child on The Simpsons, playing the role of Greta Wolfcastle, the daughter of movie star Rainier Wolfcastle. She is another one of Bart Simpson’s loves, even though he dumps her for being too needy. He’s not too happy when she starts dating Milhouse, though.

9 It Wasn't Robert Pattinson Who Played The Vampire Edmund, But Daniel Radcliffe

Daniel Radcliffe As Edmund
Taringa.net

Casting Daniel Radcliffe to play a vampire named ‘Edmund’ is so typical of The Simpsons’ humor! Of course, Radcliffe is famous for playing Harry Potter, pop culture’s young-adult fantasy rival character to Twilight’s Edward Cullen. While Edmund appears to be eight, he’s actually 400 years old, making him just a little inappropriate for Lisa.

RELATED: 15 Things That Really Happened Behind The Scenes Of The Simpsons

8 Who Else But Lea Michele Could Play The Talented Singing Sarah?

Elementary School musical the Simpsons
Sneak Peek

You can’t have a Glee tribute on The Simpsons and not cast Lea Michele! We almost forgot that she played Sarah in the episode ‘Elementary School Musical’. In the episode, Lisa attends a performing arts camp where she meets Sarah and her fellow campers Amber Riley and the late Cory Monteith (also from Glee).

7 The Coyote's Iconic Voice Could Only Belong To One Soul--The King Of Country Music, Johnny Cash

Johnny Cash on The Simpsons
TV Club - The AV Club

You might have been wondering why the spirit guide that Homer meets during his pepper-induced delusion has such a deep voice for such a little coyote. It’s because he was voiced by none other than the country music icon Johnny Cash. The coyote delivers Homer some pearls of wisdom, just like we suspect Cash would have in real life.

6 Kim Cattrall Is Used To Playing Successful Women Like Chloe Talbot

Kim Cattrall on The Simpsons
IMDb

Sex and the City star Kim Cattrall is used to playing strong, independent women. Aside from playing Samantha Jones, she also appeared in The Simpsons' episode ‘She Used to Be My Girl’ where she starred as Marge’s old friend and now super successful journalist, Chloe Talbot. Lisa looks up to Chloe at first, but ultimately knows that Marge is her role model.

5 Danny DeVito Reprises His Role As Herbert Powell

Homer and Herbert Powell
IMDb

Danny DeVito appears a few times throughout the show’s run, returning to reprise his role of Herbert Powell. First seen in the episode ‘Oh Brother, Where Art Thou?’, Herbert is Homer’s long-lost half-brother. At first, he’s overjoyed to get to know Homer. But then, as you’d expect, Homer ruins his life.

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4 Michael Jackson Didn't Credit Himself After Starring As Leon Kompowsky

Michael Jackson in The Simpsons
Rolling Stone

At the time that Michael Jackson played the character of Leon Kompowsky in ‘Stark Raving Dad’, he was so famous that he decided against using his real name in the credits. His character, who looks nothing like him, sings Lisa one of the world’s most memorable renditions of Happy Birthday.

3 Bart's Ballet Teacher Even Looks Like Susan Sarandon

The Simpsons Bart does Ballet
YouTube - Craig Owen

Susan Sarandon is known for her great voice talents. She’s a little hard to recognize when she appears in The Simpsons, because she plays Bart’s ballet teacher with a thick European accent. But thanks to the teacher’s thick and curly ginger locks, she kind of looks like Sarandon!

2 Of Course, James Earl Jones Is The Narrator Of An Early Simpsons Episode

The Simpsons aliens
IMDb

James Earl Jones has voiced multiple characters on The Simpsons and first appeared in the very first ‘Treehouse of Horror’ Halloween special. In the episode, he voices the delivery man, the alien called Serak the Preparer, and, of course, the narrator of Edgar Allan Poe’s ‘The Raven’.

1 Maggie Simpson Can Speak After All, And She's Voiced By Elizabeth Taylor

Maggie's First Word
YouTube - William Adens

As it turns out, Maggie Simpson does have a voice. In the episode ‘Lisa’s First Word’, she utters her first word, unbeknownst to her family members: daddy. The late Hollywood legend Elizabeth Taylor was the perfect person to voice the youngest Simpson as she speaks for the first time.

NEXT: 20 Times The Simpsons Predicted The Future And Freaked Us All Out