Greta Gerwig and partner Noah Baumbach have joined forces again for new coming-of-age movie Mistress America. Keeley Bolger finds out about teenage insecurity, having a voice and why female relationships are so integral to their stories...

From The Breakfast Club in the Eighties, Dazed And Confused and American Pie in the Nineties and, more recently, Ghost World and An Education in the Noughties, every generation has their big-screen coming-of-age drama.

Usually centred around awkward teens (who discover their deeply buried confidence just before the credits roll) or those with a misplaced confidence (who are actually more troubled and vulnerable than they first appear), this summer's indie-comedy Mistress America takes a sideways glance at growing up.

Here, it's first year student Tracy - played by Lola Kirke, who was born in London but raised in New York - who is the awkward teen struggling to find her place in the world, which in this case, is university.

Self-conscious and a little lonely, she is neither fitting in as well as she hoped, nor living the metropolitan life she thought moving to New York would bring.

Fed up with her lot, Tracy calls on her soon-to-be stepsister Brooke, played by Greta Gerwig, who transforms her life.

Charismatic girl-about-town Brooke, who is a decade older than Tracy, soon opens up her world.

But what else should you know about the film? Here, real life partners Gerwig and Noah Baumbach who co-wrote the movie (Baumbach also directed it), open up about putting women at the heart of their story...

UP THE WOMEN

Mistress America is an unusual film, in that it celebrates a relationship between two women, who talk about things other than men.

Gerwig - who starred in 2012's Frances Ha, which she also co-wrote with boyfriend Baumbach - was determined to address this imbalance.

"It's a very conscious decision to make films where the central relationship is between two women," says the 32-year-old, who was born and grew up in California, and will also be seen in new comedy Maggie's Plan, with Julianne Moore, later this year.

"I have such a myriad of relationships with women. Whether it's my sister and I, my mother and I, my best friend or someone I've just met who I think is amazing, I want to document those experiences in some way, because I feel like they're often under-represented or just a secondary thing that we don't even focus on."

GROWING PAINS

Like Tracy, both Gerwig and Baumbach say they felt insecure as teenagers.

"I was nervous and unsure of myself, but also like Tracy, I was secretly confident," explains Gerwig.

"I think one of my favourite scenes is when Tracy says, 'Sometimes I think I'm smarter than everyone and if I could figure out my look, I'd be the most beautiful woman in the world'.

"I think that's such a hilarious sentiment for an 18-year-old girl who has not shown any signs of being that person who she thinks she is. I don't know that I would have been able to articulate that so clearly, but I had some combination of being insecure and also wildly ambitious."

TOGGED UP

To help exact upon Tracy's look and help Kirke get into character, Gerwig opened up her wardrobe to the upcoming actress.

"We actually put Lola in a bunch of my clothes from when I was 18," says Gerwig of Kirke, whose sister Jemima plays Jessa in hit US series Girls.

"We put her in my big, oversized blazers and berets."

WORKING RELATIONSHIP

As well as being creative partners, Baumbach and Gerwig are in a relationship and, as such, often find their conversations drifting into work territory, even when they're away from set.

"If we're working on something, it's hard not to break at any point and say, 'Wouldn't it be great if we did X, Y and Z, even if we're having dinner or talking about something else,' admits Baumbach.

"The ideas seem to be all around when you're in the middle of something. But when we're not writing something, it's easy to talk about other people's movies."

THE VOICE

While writing and co-producing comes with responsibility, Gerwig is proud she found the confidence to commit pen to paper.

"For me, taking the leap and allowing my voice to be heard as an author has been huge," says Gerwig, whose other writing credits include 2010's Northern Comfort and 2007's Hannah Takes The Stairs.

"I kept worrying people would say, 'You have nothing original to say. You have no voice. You have no business telling your story', but the fact that, by and large, people tend to say, 'I'm interested', and, 'I want you to keep story telling'... That's huge."

Mistress America is released in cinemas on Friday, August 14