Age 15 is the height of hormonal angst and adolescent gawkiness. Greta (Bethany Whitmore) has overbearing parents and is the victim of elaborately orchestrated bullying tactics. But Greta’s experience becomes peculiar when she wanders into another dimension: a surreal forest of fantastical creatures.

An entirely Australian production, Girl Asleep is a coming-of-age film that’s garnering international attention.

Girl Asleep marks Rosemary Myers’s directorial debut (on screen, at least). Myers is artistic director of Adelaide’s Windmill Theatre. The pioneering theatre company has always focussed on themes of childhood, adolescence and family. In doing so Myers and her collaborators explore growing up.

“It’s an amazing time of life,” Myers says. “You’re dealing with massive ideas of identity, and you’re kind of understanding where you fit in the world.

“I think back to my teenage years … I was just growing up in the suburbs, and probably nothing that radical happened. But life felt like it was really high-stakes at that point. It’s a formative time for people. It can be quite harsh, quite violent.”

Girl Asleep is much more than a criticism of adolescence’s cruelty, thanks mostly to stunning production design. Production and costume designer Jonathon Oxlade has created a lush mirage of ’70s Australiana (Greta’s family home is filled with the very best of Salvation Army bric-a-brac). The film is clearly influenced by the pastel-heavy world of Wes Anderson. In both style and theme comparisons can be drawn between Girl Asleep and Anderson’s coming-of-age film, Moonrise Kingdom.

As the story enters Greta’s hallucinatory forest a completely different visual experience begins. Impossibly colourful and meticulously detailed costumes adorn the creatures of the forest. These strange, confronting sequences are the defining moments of Girl Asleep.

“We wanted to play with the forest as a metaphor for the teenage years,” says Myers. “In fairy tales, the forest is a liminal space – a place of transformation. We wanted to play with the idea that all teenagers go through that forest, and their experiences through that forest can be very different.”

Girl Asleep features a number of charming performances – most notably by Matthew Whittet, the film’s writer, who dominates the screen as Greta’s goofy father. But this cast of (mostly) teen performers is prone to clunky deliveries and missed-beats. Moments of would-be drama are unintentionally comic: schoolyard bullies are hardly intimidating; confessions of love are awkward in all the wrong ways; tender moments are overacted, to the point of cringe. These faults are further exacerbated by clunky editing decisions, which disturb the film’s playful rhythm.

Despite its unpolished moments Girl Asleep is a fun viewing experience. It premiered to unprecedented popularity at the Adelaide Film Festival in 2015. This year the film has screened in Berlin, New York, Buenos Aires, Stockholm and won the Grand Jury Prize at the Seattle International Film Festival. Myers’s first foray into cinema has proven a rewarding experience.

“Theatre is very ephemeral,” she says. “Once it’s over, once you take the bow, that’s the end. We do tour our [stage] work a bit, but Girl Asleep is something that will have an ongoing life.”

Girl Asleep is now screening in selected cinemas.