Season 3, "The One with the Jam"
Friends star Courteney Cox's future husband guest starred on the show in season three, striking up an unlikely romance with Phoebe. Arquette played Malcolm, the stalker of Phoebe's twin sister Ursula. He mistakenly stalks Phoebe and the two become interested in each other.
Season 2, "The One with the Chicken Pox"
The future Two and a Half Men star played Phoebe's "submarine guy," Ryan. As he's on land for only a short time, he and Phoebe have made plans for some lovely alone time, but find it ruined by the chicken pox.
Season 4, "The One with Ross's Wedding"
Before his days on House M.D., Laurie played the man on the airplane who sits next to Rachel on her way to London. While she's a ball of energy as she works up the nerve to break up Ross's wedding, Laurie's a bit more toned down. He's hilariously rude to her and his performance is one of our favorites in the show's history.
Season 2, "The One After The Superbowl"
This season 2 episode aired immediately after Super Bowl XXX and had a ton of stars in it. Singer Chris Isaak, action star Jean-Claude Van Damme, Simpsons star Dan Castellaneta, and comedian Fred Willard also appear in the episode, but it's most notable for its leading ladies: Julia Roberts & Brooke Shields. Roberts plays Susie Moss, Chandler's old schoolmate who, thanks to Chandler, became known as 'Susie Underpants' for most of her childhood. And she wants revenge -- underpants, Mr!
Season 10, "The Last One"
The Academy Award-winning Community star made an appearance in the series finale, playing the nervous male passenger on the plane next to Rachel. One could even argue that it's his nervousness that's responsible for Ross and Rachel finally getting together. His fear that something is wrong with the left phalange, just like Phoebe predicted, caused him and everyone else flee from the plane, buying Ross enough time.
Season 7, "The One with Joey's New Brain"
Susan Sarandon plays Jessica Lockhart, one of the stars of Days of Our Lives who is being written out of the show and whose character's brain is transplanted into Joey's characters. Naturally. Sarandon shows Joey the ropes of her character in order for him to play her properly. She teaches him the art of throwing a drink at someone and slapping them in the face (which she also teaches her daughter, Eva Amurri, who also appears in the episode).
Season 4, "The One with the Dirty Girl"
Before she became X-Men's Mystique, Romijn received her first ever acting role as Cheryl, the titular Dirty Girl in this episode of Friends. She and Ross are dating, and even though she's physically flawless, Ross can't get over how filthy her apartment is.
Season 7, "The One with Ross and Monica's Cousin"
Richards turns up in season 7 as Cassie Geller, Ross and Monica's cousin who is in town for their wedding. Except, she's slightly put off by the fact that she's become the object of affection for her cousin's fiancé, Chandler. And her cousin, Ross. And their friend, Phoebe. Honestly, it's not their fault they can't stop staring at her -- you would too if you saw Denise Richards in slow motion, wouldn't you?
Season 7, "The One with Chandler's Dad"
Kathleen Turner plays Charles Bing, aka Helena Handbasket, Chandler Bing's father who has his own Las Vegas show. We can't decide which of Chandler's parents are more fabulous.
Season 1, "The One with the Blackout"
In one of the first episodes of the show, Chandler is trapped. in. an. ATM. vestibule. with. Jill Goodacre. And for that, Jill Goodacre's appearance as herself is iconic.
Season 1, "The One with Two Parts"
The ER heartthrobs appear together on Friends as Dr. Michael Mitchell and Dr. Jeffrey Rosen, the doctors who treat Rachel for her sprained ankle. They also ask the girls out on dates only to be turned off by the confusion and bickering caused by their switching identities in an insurance fraud scheme.
Season 10, "The One with the Birth Mother," & 4 Others
Faris guest starred in the final season of Friends as Erica, the birth mother of Monica and Chandler's babies! She wasn't the smartest, but she gets points for bringing the Bings their babies!
Season 7, "The One with the Cheap Wedding Dress"
The Bring It On star played Kristen Lang in this season 7 episode. Both Ross and Joey meet her as she's moving into her apartment and ask her on dates, and then fight over her while on a date with her.
Season 1, "The One with Two Parts"
Helen Hunt made a cross-over appearance on Friends, starring as her Mad About You character Jamie Buchman. Jamie walks into Central Perk and mistakes Phoebe for her twin sister, Ursula, who is a waitress on Mad About You.
Season 9, "The One with the Mugging"
The Jurassic Park star played a legendary director Leonard Hayes, who initially doesn't like Joey for the part in his play, but, after Joey drinks too much, begins to like his needs-to-pee energy in the scene. Goldblum ends up getting drenched in Joey's excess...energy.
Azaria and Rudd each played Phoebe's two greatest loves: David, the scientist guy who left her to go to Minsk, and Mike, the piano player who ended up marrying her. They played two of our favorite characters on the entire show, and we're sad that they both couldn't somehow have won Phoebe's heart (but we're still totally #TeamMike).
Season 7, "The One with Rachel's Big Kiss"
The Girl, Interrupted star plays Melissa Warburton, a former sorority sister of Rachel's who Rachel claims she made out with in college. When Phoebe doesn't believe her, Rachel goes to dinner with Melissa and brings Phoebe along, but Melissa denied the kiss ever occurred. Finally, Melissa admits the truth and grabs Rachel for a long-awaited kiss. Obviously, with two ladies as beautiful as Ryder and Aniston locking lips, this appearance was quite memorable.
Season 6, "The One Where Ross Meets Elizabeth's Dad"
Legend has it that Bruce Willis only appeared on Friends after losing a bet to Matthew Perry on the set of their movie, The Whole Nine Yards. The bet turned out to be worth it though, because he won an Emmy for playing Paul Stevens, the father of Ross's college girlfriend Elizabeth.
Season 2, "The One After The Superbowl"
Shields plays Erika Ford, Joey's stalker -- sort of. The deranged beauty thinks she's dating his character from the soap opera Days of Our Lives, and becomes dangerous when she's convinced Joey actually is neurosurgeon Dr. Drake Ramoray.
Season 2, "The One with Frank Jr."
The Italian beauty plays herself in this episode. Ross creates a list of female celebrities he would be allowed to cheat on Rachel for, but bumps Rossellini for somebody less international. When the Blue Velvet star walks into Central Perk, he regrets that decision in a major way.
Season 7, "The One Where Rosita Dies"
The Seinfeld alum plays Earl, whom Phoebe calls during her first day as a toner-selling telemarketer. Earl plans to kill himself and Phoebe is left trying to talk him out of it.
Seasons 1 & 9, "The One with the Stoned Guy" & "The One with the Blind Dates"
The former Saturday Night Live cast member plays Phoebe's friend Steve on the show. In season 1, Steve is opening a restaurant and wants to test Monica's cooking, but may have gotten too stoned. In season 9, he's back, this time on a blind date from hell with Rachel. Both appearances are laugh-out-loud enjoyable.
Season 3, "The One with Mrs. Bing"
Nora Bing is an erotic novelist and a full-fledged MILF, but we wouldn't want this sassy and successful woman as our mom, especially not if she'd be making out with our friends like she did to Chandler's. We still can't decide whether she's more fabulous than Chandler's father or not though. She did bring Jay Leno for a guest appearance her first time on the show, and that's pretty baller.
Season 3, "The One with the Ultimate Fighting Champion"
There's no real explanation for these two appearing on the show (except perhaps to promote their film, Father's Day), but we are so glad they did. Their conversation - discussing Williams' wife extra-marital activities - even catches the attention of the Friends crew. It's definitely the best guest appearance.
Season 7, "The One with Ross's Library Book"
Joey takes home the Sex and the City star just like he would any other girl. Only, this time, his roommate Rachel and their friend Phoebe intercept her and become best friends with her. That's what happens with Joey's date, Erin, and he's left to deal with the mess of it.
Season 10, "The One with Ross' Grant"
Kinnear plays Ross's girlfriend Charlie's ex, Dr. Benjamin Hobart, who also happens to be the man who decides whether Ross gets his grant money or not. Dr. Hobart, "Benji" to Charlie, is more than willing to give Ross the money, if Ross breaks up with Charlie.
Seasons 2 & 8, "The One with the Lesbian Wedding"
The TV icon, famous for her role as Ann Marie on That Girl, Marlo Thomas plays Rachel's mother, Sandra Green, who is completely awesome as a guest star. She visits her daughter, announces that she wants a divorce, asks what's new in sex, and then asks for some marijuana. Just like you wish your mother wouldn't.
Season 8, "The One with Rachel's Sister"
The Oscar winner plays Jill Green, Rachel's bratty younger sister who ends up going on a date with her big sister's ex Ross.
Season 8, "The One with the Rumor"
Jennifer Aniston's then-husband (#heartbroken) Brad Pitt guest starred on Friends as Will Colbert, a high school classmate of Rachel, Monica, and Ross's. Ross and Will used to hate Rachel back in high school, and he spends the episode looking sexy and angry as he explains the rumor he started about her in high school.
Season 10, "The One Where the Stripper Cries"
Living legend Danny DeVito plays Ron the stripper, the old, not-that-sexy stripper that Rachel and Monica hire last minute for Phoebe's bachelorette party. What starts as an unpleasant experience on the eyes becomes a heartwarming conversation and a dance that Phoebe seems to think is pretty hot. Overall, a magnificent guest appearance.
Season 8, "The One with the Halloween Party"
The two-time Academy Award winner played Eric, Ursula's fiancé that maybe didn't know Phoebe's twin as well as he thought he did. He also was a second grade teacher that showed up to Monica and Chandler's Halloween party as the solar system, which gives him major points in our book.
Season 8, "The One in Massapequa"
The 30 Rock star appeared in two episodes as Phoebe's boyfriend Parker, an overenthusiastic and exhausting creature of a man who refers to the Long Island Expressway as a "concrete miracle." He also forces Phoebe to eat an oyster. While he was brilliantly funny, he's so effective at being annoying that the episodes themselves could make a viewer homicidal.
Season 9, "The One with Christmas in Tulsa"
The Cruel Intentions star played seductress again in this holiday Friends episode. Blair plays Wendy, one of Chandler's coworkers in Tulsa who steals a ham from a party and then throws herself at Chandler like a genuine Grinch, ruining Christmas.
Season 9, "The One with the Donor"
The Full House heartthrob made an appearance as Zack, one of Chandler's coworkers who seems to have desirable sperm. Chandler invites him to dinner with Monica and the two harass him with sperm-related questions without him knowing.
Season 9, "The One with Rachel's Other Sister"
It's hard to top Reese Witherspoon's appearance as Jill Green, Rachel's other younger sister, but somehow Christina Applegate managed to. Her turn as Amy, who can't remember any of Rachel's friends, nor the name of Rachel's baby, is hilarious. She appears in two episodes in later seasons. The first , a Thanksgiving episode that ends in a sister slugfest, features Amy trying to get custody of Emma if Ross and Monica die, and earned Applegate an Emmy. The second time, she babysits and pierces Emma's ears.