For her first effort as a writer-director, Marielle Heller tackled a phenomenal number of tasks. To make The Diary of a Teenage Girl, which opens here Friday (August 14), the native Californian first spent several years lobbying artist Phoebe Gloeckner for the rights to her edgy 2002 graphic novel of the same name.

Then she turned the work into a play with herself in the lead role as 15-year-old Minnie Goetze, adrift in mid-’70s San Francisco. Meanwhile, she developed that as a screenplay with the Sundance Institute, where she got to work with Lovely & Amazing director Nicole Holofcener and others.

This eventually became the movie, with Kristen Wiig as Minnie’s troubled single mom and British newcomer Bel Powley as the freethinking teen who has a disturbing affair with Mom’s 35-year-old boyfriend, played by Sweden’s Alexander Skarsgård.

It was already challenging to present nascent sexuality in such a naked and starkly nonjudgmental form. (Gloeckner is also a successful medical illustrator, by the way.) But Heller also took on the labour-intensive task of conjuring up the San Francisco of 1976. And she nailed it.

“It felt like going home,” says the filmmaker, calling the Georgia Straight from New York City. “I grew up in the East Bay, in Berkeley and Alameda, and I felt an obligation to get it right when it came to re-creating the world I was born into. Maybe because of TV shows from that period, people tend to think of it as much more colourful than it was. Also, San Francisco held on to the ’60s a lot longer than other cities did.”

In her research, which, of course, included various older family members, she found that earth tones ruled that Birkenstock world. “Yes,” she says with a laugh, “I realized that brown was the old black; wherever people would wear black today, I substituted brown and beige.”

There’s some orange and avocado in there, to be sure, and lots of India ink, to suggest the underground comix scene that inspired Minnie (and Gloeckner). With all that specificity of time, place, and peculiar milieu, believable accents were a must, especially for Powley, who has a thick Cockney drawl in real life, and Skarsgård (son of the great Stellan), whose Scandinavianisms would only occasionally creep in.

“We had a dialogue coach early on, but basically I just had to ride Bel on the set to get certain idioms exactly right. I think this is where my own training as an actress paid off,” explains the filmmaker, who previously appeared with Wiig in MacGruber, directed by Heller’s husband, Jorma Taccone, with whom she recently had her first child. “It wasn’t until I got to acting school, at UCLA, that I even knew I had a California accent and that it was something that could be learned.”

Only 35 herself and recently named one of Variety’s top 10 directors to watch, Heller will next tackle the early years of U.S. Supreme Court justice Ruth Bader Ginsburg.

“I didn’t write the script,” she avers, “but it certainly fits with my intention to make films about strong, complicated women.”

When asked if anyone is already attached to that ambitious project, she says, “No, just Natalie Portman.” Yeah, just Natalie Portman.