Lizzy Caplan has built a career out of playing salty sidekicks: the goth foil Janis in Mean Girls, the cater-waiter-coworker-with-benefits in Party Down, a love interest in Hot Tub Time Machine, and a hallucinated sister in 127 Hours. In her new show Fleishman Is in Trouble, Caplan’s character too, starts out on the sidelines. Adapted by Taffy Brodesser-Akner from her 2019 novel of the same name, the FX on Hulu limited series initially centers on nebbishy Manhattan surgeon Toby Fleishman (Jesse Eisenberg) and his imploding marriage to mega-agent Rachel Fleishman (Claire Danes). Caplan plays Toby’s old college friend Libby Epstein, a former magazine journalist now floundering in suburban stay-at-home-mom exile. Ever so gradually, it becomes clear that though someone else’s name is in the title, Libby is closer to the center of the story than she or the viewer first realizes. She’s also the series’ narrator, overseeing the action throughout like the Voice of God.

“In early conversations, Taffy wanted to reassure me that there was a payoff for Libby,” Caplan recalls, chatting with Vanity Fair by video from her Los Angeles home, where her infant son’s howls occasionally can be heard from the other room. She needed no reassurance about the role. Having so much experience with spicing up secondary characters, Caplan knew how to wring substance out of a brainy, marginalized figure like Libby.

“In many ways, I identified with Libby more than I’ve identified with any other character I’ve played,” Caplan says. “It’s like the East Coast version of my West Coast Jewish upbringing.” She laughs when I point out that she’s one of the rare celebrities whose Wikipedia page makes note of their Bat Mitzvah and Jewish summer camp pedigree—her ancestors would be kvelling! Fleishman’s mostly Jewish cast startled her. “I’ve never once been on a set with all Jewish actors—not once!”

Another element that connected with Caplan is her character’s growing understanding of how misogyny shaped her career. Magazine journalist Libby believed herself to be one of the guys and expected to be judged on merit—but the “guys” always saw her as an outsider. “The one of the guys thing…I was that girl, which now is such an eye roll to me,” Caplan says, without rolling her eyes.

Caplan’s career fate was sealed at the age of 15, after she took an acting class at her Los Angeles performing arts-focused high school and caught the bug. She found a manager’s assistant who sent her on a flurry of auditions. “In my mind, I was going to land the leading role in everything immediately…a lot of Shakespeare, and heavy-hitting Oscar fare,” she says self-mockingly. “Then I booked my first job, which was Girl #1 in the pilot of Freaks and Geeks. I had one line, and I remember being like, Should I do this? Luckily, they convinced me that yes, I should do this. And, miraculously, that became a recurring thing.”

Fox famously canceled Freaks and Geeks after a single season, and Caplan discovered that Hollywood of the early 2000s was not craving idiosyncratic, barbed-tongue young women for lead roles. She is grateful for that now. “When you start acting so young, you’re figuring out who you are too. And it’s why it’s so dangerous if you actually do become really famous,” she says, hugging her knees to her chest. “You’re fixed as this thing that you were chasing when you were fucking 16. No teenagers should ever be actors!” But Caplan says she lucked out, because Freaks and Geeks set her on the right path. “Before I had any agency at all, before I could make any decisions on my own, I was kind of put on this trajectory that I am on. I don’t know how it happened. It’s like some cosmic thing that I’m honestly forever grateful for because it could have gone any number of different directions.”

Her first big movie, Mean Girls, made her an icon to snarky goth girls like me, who rarely saw versions of themselves in pop culture back then. Wary of being pigeonholed as a broody misfit, Caplan briefly tried her hand at being an ingenue on the youth-saturated WB network, dying her hair blond and sporting a spray tan for the series Related. “I remember wanting to be in Smallville more than anything,” she says with a husky chuckle of another WB show she appeared in. “I could have ended up living in Vancouver for 10 years and potentially would have been the number two of the NXIVM cult!”

Caplan thought she’d landed her big break in 2006, when she was cast in The Class, an ensemble comedy from Friends cocreator David Crane that was expected to be a monster hit—to the point that director James Burrows flew the whole cast on a private jet to Las Vegas and gave them the same speech about stardom that he’d delivered to the Friends actors before that show premiered. “It was heartbreaking at the time,” she admits but says she’s never really yearned for mega-fame.

I ask her if her six-year relationship with Matthew Perry post-Friends contributed to that distaste for stardom. “I was never interested in that life,” she says, sipping on the dregs of an iced drink. Perry doesn’t mention her by name in his new memoir, but he does throw in an odd, oblique anecdote about a “woman I’d dated for six years” who went on to date a British guy. (Caplan married British actor Tom Riley in 2017.) Not only did this ex decline an invitation to attend his debut play in London, he writes, but “a while later I got back an email telling me that she was getting married and that she had no room in her life for friends.” Caplan says she hasn’t seen the book and smiles placidly when I relay the anecdote. “I don’t remember that! I really don’t know much about the book or anything.” She shrugs. “You know, I have no ill will. I hope the book is really successful.”

Having witnessed the sour side of stardom already, Caplan’s own ideal career is one that allows her to seek out roles that freak her out, like playing Virginia Johnson in the Showtime series Masters of Sex. “Maybe that’s a benefit of not being in the uppermost stratosphere of fame, where there’s an expectation from the public of what type of actor they want you to be.” She continues, “The only level of success that’s really nice is when you can get a good table at a restaurant—that’s the zone.”

Not that Caplan has much time for fine dining, what with a baby at home and a relentless work schedule. Caplan just finished shooting a TV reboot of Fatal Attraction for Paramount+, reimagining Glenn Close’s Alex Forrest character. She won’t tell me anything about how the character has been revamped for 2022 but she is boggled by how far we’ve come from the 1980s culture of the original. That you could make a movie about a married guy who cheats on his wife with this single woman, she points out, “and somehow the audiences were all like, That bitch needs to die! How dare she?” Caplan shouts. “If you watch it now, it’s really difficult to even see it in that way…. It is bonkers, the Michael Douglas character doesn’t even apologize!”

Caplan has been so busy that she missed the chance to appear in the Starz revival of cult series Party Down. “It’s horrible,” she says, looking stricken. She says she offered to go back and forth between the Fleishman shoot in New York and Party Down in LA, but it was too difficult for the productions to coordinate in advance. “I just ran into Ryan Hansen from Party Down in a pumpkin patch and we had a little weep about it. I love them all so much.”

During the pandemic, Caplan also started developing her own projects with her husband. “It was a combination of the lockdown and just, like, getting older,” she says. “At a certain point, if you have a brain in your head and you are an actor, you realize that maybe you don’t want to sit around and wait for somebody to give you opportunities. So hopefully these things come off because they’re all very fucking cool, left-of-center, female-driven projects.” While she embraces the current cultural environment that allows for the Libby Epsteins and Alex Forrests to have their say, Caplan can’t help but feel a little cynical. She was struck by Libby’s theory in Fleishman that men put up with girls wearing “Future Is Female” T-shirts because it’s a lie that makes their marginalization bearable. “It’s like everybody’s in on this joke…and if it were actually true, there’s no way we’d be allowed to wear the fucking T-shirt,” she tells me wryly.

Much of Libby’s career as a men’s magazine journalist seems loosely inspired by Brodesser-Akner’s own years working for glossies like GQ, but Caplan sees the character as pretty universally relatable, media or no. “As well as rolling with the guys and being cool with everything, Libby was really responsible and did everything right and filed her stories on time.” There’s so much less leeway for women to fuck up or careen off the beaten path, whether in journalism, entertainment, or elsewhere. “I think about that all the time with actors,” Caplan says. “You don’t hear a lot about women method actors, especially those with families. There’s no room for art to trump everything in many women’s lives. You come home and you’re the mom—you don’t still get to [live as] the junkie streetwalker or whatever you were playing at work.” She quickly points out that she never had method-acting ambitions, “but if I wanted to be, I don’t think that is a real option!”

Although she feels enormous kinship with her Fleishman character, Caplan points out that she and Libby are at very different life stages. “[Libby] feels very trapped in her life, and I started shooting the show when I was a new mother to my first baby,” she says. “The domestic side of my life was completely exciting and fulfilling. I mean, it’s only been a few months,” she cracks. “But there’s no part of me that felt like my real life was stale or stifling in any way…. I was getting to have this very fulfilling acting gig at the same time that I was fulfilling these lifelong domesticity dreams that I kicked down the road for so long.”

A native Angleno who grew up in the center of the city, she does find herself seduced by suburbs like Nyack, New York, where she shot some Fleishman scenes. “It looks like the ’80s movies I watched when I was a kid—like a throwback to a simpler time,” Caplan says wistfully. “But Taffy was like: ‘Don’t. Do. It!’”