IN CULT TV series Girls , Hannah Horvath & co tried to make it as grown-up New Yorkers and fell short of the mark. So when Mimi-Rose Howard turned up in series four, she made an immediate impression. A confident, in-control performance artist with a perfect model half-bun, Mimi-Rose was mature, independent and flourishing. Hannah, who had bad hair and little success, couldn’t help comparing herself.

Mimi-Rose was intimidatingly good, a characteristic shared by the actor who played her, Gillian Jacobs. At 35, she has Juilliard School cred, calls Lena Dunham her friend and has won approval from uber producer Judd Apatow, who cast her in his modern Netflix romance, Love . The streaming service was equally impressed, and made her the lead in its big summer comedy this year, Ibiza .

But the reality of success, says Gillian on the phone from her home in LA, was always more Hannah Horvath than Mimi-Rose. ‘I kind of faked it until I made it,’ she says, laughing off the idea of hitting her stride in New York and then hitting the big time. ‘I still struggle with it. It’s not something I think I’ve solved.’ It’s something she’s written about before – on confidence, setbacks and adulting – in a piece for Lena’s Lenny Letter, entitled ‘Learning How To Act Like Myself ’.

For a long time, Pittsburgh-born and raised Gillian was most successful when she acted like someone else entirely. She was great when cast against type, like when breaking out in the meta 2009 US sitcom Community , where she played a vacuous high school drop-out. In reality, Gillian only ever skipped class once – to visit a museum. After Girls , Judd Apatow cast her as the messy AF Mickey in Love in 2016, which ran for three series on Netflix. Mickey was a love, sex, drugs and alcohol addict. In real life, Gillian lived such a sheltered existence that she didn’t know how to act flirtatious for an audition. A teetotaler, she’d never touched a drop of alcohol.

as Mickey in Love
with Adam in Girls
her big break, Community (PHOTOS: ANAIS & DAX/AUGUST)
her new project Dean
with Phoebe Robinson in Ibiza

This year, she’s playing characters closer to her sensible self. She’s the grown-up in Dean, a dramedy in which her character wisely decides against a romantic entanglement with a grieving young illustrator. And in Ibiza, she’s a New York PR whose friends railroad her into a wild weekend on the White Island, which is something the actor would never do in real life. Instead, the self-proclaimed theatre nerd enjoys nights in, reading historical fiction (she’s a huge Hilary Mantel fan) and going out for food. She won’t cook for herself at home. ‘Otherwise I would never leave the house,’ she laughs, by way of explanation.

Gillian is an only child who, as a kid, preferred spending time with grown-ups, reading Shakespeare and listening to public radio, rather than hanging out with children her own age. There were problems at home. Her dad was an addict (he’s the reason she’s never drunk alcohol) and her parents split when she was two. She was brought up by her single mother and her dad has since passed away.

Acting class, aged eight, presented itself as a safe space from bad adult drama. ‘The first time I stepped into an acting class, I felt like I finally belonged,’ she says. ‘I was good at it and everyone there was nice and accepting of me. It gave me a sense of belonging, which I never really had before.’

In one way, Gillian was acting all grown-up: she has described herself as more mediator than child to her parents. But in another, she was quietly retreating into herself. ‘Having a parent who is an alcoholic gives you a sense as a kid that you’re a little bit on your own,’ she says. ‘You can’t really trust the adults in your life to be there for you so it made me really internalise everything. It was better if I kept everything to myself because I didn’t always get what I needed from parental figures.’

Gillian is at ease enough to move between such emotional honesty and wisecracking, which demonstrates why she’s such a go-to for comedy with feelings. ‘Have you talked to my therapist?’ she laughs when the conversation takes a turn for the psychiatrist’s couch. But it’s taken a long time to reach a comfortable place. At college, she still looked to the adults for validation. On paper, she was the ideal student. She was academic and obedient and would even spend college holidays taking extra courses at Harvard and the University of Chicago. She hasn’t lost her scholarly streak; in-between filming Love, she swotted up on computing pioneer Grace Hopper for a short film she wrote and directed.

But stage school proved problematic. Juilliard tutors seemed to want her to loosen up, be exposed, get out of her head. Gillian thought the faculty were trying to tell her who to be – a ‘big strong woman’, when in reality she was still a teenage girl. The experience rattled her but proved instructive, eventually: ‘What Julliard gave me in part was to stop looking to authority figures for approval as much,’ she says now. ‘If I didn’t need validation from people so desperately, then I could handle the bumps a bit easier.’

Post-college was not exactly plain sailing. She and her friends dined out on dollar pizzas, in part to avoid sitting around their dingy New York apartments. She did theatre but – confidence knocked – she gravitated towards TV and cinema because she didn’t feel deserving of the prestige stage roles. This, even though The New York Times called her ‘a star in the making’. She went through a phase of auditioning for roles that called for her to be a ‘conniving, sexually manipulative woman’. She would go to the Bobbi Brown make-up counter in Barneys to do her make-up and buy push-up bras because she wasn’t used to doing glamour. She flunked out plenty of times. If it sounds all very Girls, that’s because it was.

Gillian met Lena through a mutual friend in New York, who was working on the latter’s first film, Tiny Furniture. Lena and showrunner Jenni Konner had Gillian in mind for the role of Mimi-Rose, which she found out about when she stumbled upon the Girls crew shooting on location in New York and they got talking. She was already established as a comic actor by then with Community but Lena gave her more than just another role to shine in. The confidence Gillian invokes to be vulnerable in public she puts down to her warts-and-all friend. ‘I was hesitant to do that,’ she admits of putting down in words her feelings. ‘I didn’t know if I was capable of it. I have to credit Lena with that entirely because I don’t know if I would have started writing personal essays or started to do interviews without her.’

New York also taught Jacobs to keep going. To act like a grown-up, even when she didn’t believe it. ‘Someone said to imagine yourself as the CEO of the corporation of you,’ she explains. ‘The thing that was best for the business of Gillian Jacobs was to keep going no matter how many times I got rejected. To always keep at it and not give up.’ She laughs, uproariously, at this point. ‘Even if I didn’t always feel like that.’ ‘Ibiza’ is streaming on Netflix now, and ‘Dean’ is available on digital download in the UK now