In a lot of ways, NBC’s Friends was the definition of television success. We’re talking about one of the longest-running ‘90s sitcoms in Hollywood history. Throughout its run, Friends earned 62 Emmy nods. More importantly, the show also became one of the Emmy's outstanding comedy series winners as it picked up six wins over the years.

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Today, Friends has achieved a whole new generation of fans thanks to the show’s availability on various streaming platforms. And if you plan to do another rerun of the show, we thought it would be fun to see if you can spot these Oscar winners:

Robin Williams

Tomas and Tim in Central Perk on Friends

The late award-winning actor once took his comedic chops to Friends for an episode in season three titled "The One with the Ultimate Fighting Champion". As you may have heard, the true story behind Williams’ cameo on the show is also quite interesting. Originally, the actor’s appearance alongside Billy Crystal was not on the episode’s script. However, when the men were spotted near the show’s filming location, writers approached them and asked them if they can do an appearance. Today, Williams remains a much-beloved actor. In fact, fans have even created some pieces of art to pay tribute to him.

Charlton Heston

Some may argue that there are some celebrity cameos that hurt the show, but Heston’s appearance was among those that saved it. In most cases, guest actors on the show typically take on a role. Sometimes, they’re introduced as an old acquaintance or a member of the family. Other times, the main characters appear to encounter them by chance. In the case of this Oscar winner though, he appeared as himself. In the episode "The One with Joey’s Dirty Day", Joey heads straight to a movie set from a fishing trip and decides to shower in Heston’s dressing room.

Jim Rash

Rash’s guest appearance on the show was among the last ones of the series as it occurred in the two-part series finale. In "The Last One", Rash poses as a nervous passenger who ends up sitting next to Rachel on the plane. And when Rachel starts to talk to Phoebe about a “phalange” issue, Rash’s character takes it to mean that their flight was doomed. The whole scene offered a much-needed comedic moment since fans were probably anxious about the fate of Rachel and Ross’s relationship at that time.

Helen Hunt

Helen Hunt in Central Perk in Friends

The Oscar-winning actress and filmmaker appeared during an episode in the show’s first season entitled "The One with Two Parts: Part 1". Interestingly, Hunt appeared on the show as Jamie Buchman, which is a direct reference to her role in another hit sitcom, Mad About You. So, in some ways, Hunt’s guesting was a crossover event. In the scene, Jamie walks into Central Perk and orders coffee from Phoebe. As it turns out, Jamie had mistaken Phoebe for her waitress twin sister, Ursula.

Sean Penn

If you think about it, getting this Oscar-winning actor to appear on the show was quite a feat. After all, Penn has developed a reputation for being “anti-Hollywood.” This means he doesn’t typically make himself available for tv guest roles. In the case of Friends though, Penn was reportedly willing to make an exception since his own children were huge fans of the show. In the end, Penn portrayed Eric who was Ursula’s fiancé. According to Entertainment Weekly, Penn and his family also visited the set several times.

Susan Sarandon

Joey Tribbiani and Jessica Lockhart

Sarandon has always been celebrated for her many incredible performances on the big screen, including in Dead Man Walking, which won her an Oscar. That said, there are fans who believe that the actress’ appearance on Friends is one of the celebrity cameos that don’t make any sense.

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On the show, Sarandon played Jessica Lockhart, an obnoxious actress being written out of Days of Our Lives. While speaking about her experience filming in the Friends set, Sarandon told Deseret News that Matt LeBlanc was “so sweet and patient.” She later added, “There's not a mean soul in the entire group.”

Julia Roberts

The actress appeared in season two’s "The One After the Superbowl". If you haven’t heard of the true story behind Roberts’ cameo, it starts with NBC execs determined to make sure that viewers would tune in to the show after the game. To increase those odds, they called on Roberts, an actress with enough 90s film roles for you to base your MBTI on. On the show, Roberts played Susie Moss, a.k.a. Susie Underpants, who dated Matthew Perry’s Chandler for revenge. Off-screen, Roberts and Perry were seeing each other with a spokesperson for Perry telling People, “They’ve been on a few dates.”

George Clooney

Long before Clooney won his Oscars, he played a doctor in hit medical drama ER. This is a detail you must keep in mind because it relates to the true story behind Clooney’s Friends cameo. One of the most expensive shows ever made, ER was a show that also aired on NBC.

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That said, the appearance of Clooney and his ER co-star, Noah Wyle, was not a crossover event. If you noticed, Clooney and Wyle switched ER character names with each other while on the show.

Brad Pitt

Will and Ross talk during thanksgiving in Friends.

Pitt’s appearance on the show was one of the most memorable ones that fans have ever seen. Not to mention, it was one of the funniest too. In the season eight episode entitled "The One with the Rumor", Pitt played Will Colbert, an old friend of Ross who hated Rachel. At that time, Pitt was still married to Jennifer Aniston, who portrayed Rachel. And even though the actor reportedly frequented the set, Pitt still suffered a little setback when he was acting out his part. “I flubbed my first line,” Pitt told Access Hollywood. “We had to stop and start again.”

Reese Witherspoon

The Oscar-winning actress and producer made a back-to-back appearance on the show way back in 2000. Witherspoon played the role of Aniston’s younger sister, Jill. During season six, Jill shows up and (sort of) turns Rachel’s life upside down by going out with Ross. Sadly, Witherspoon never reprised her role during the remainder of the show’s run. During an interview with Associated Press, the Oscar winner revealed she was asked back but admits, “I was like, 'I'm too nervous.” Fortunately for fans, Aniston and Witherspoon are now starring opposite each other on Apple TV+’s The Morning Show.

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