With this elegantly elliptical arthouse movie, Bai Xue announces herself as a cool, confident observer of a new generation of Chinese youth. There are echoes of Sofia Coppola in Bai’s directing debut, a coming-of-age story inspired by real-life criminal gangs in Hong Kong who recruit schoolkids to smuggle mobile phones into mainland China. It’s a wisp of film that never quite gathers speed or force but it gets under your skin, capturing the impulsiveness and impatience of teenagers. Others may find it a little flat or frustrating.

Huang Yao is shy 16-year-old Peipei, who’s frantically saving up for a holiday in Japan with her rich best friend Jo (Carmen Soup). Peipei commutes daily between her home in the Chinese city Shenzhen and school in Hong Kong. To make a little extra money she smuggles for a gang. It begins harmlessly enough, slipping a couple of iPhones wrapped in cling film into her school bag. If stopped by officials at the airport-style security on the metro, she can reasonably claim the phones are for personal use. As Peipei slips between worlds, Bai changes up the camera style, from handheld in busy Hong Kong to still compositions in Shenzhen.

What you think you’re getting here is an in-too-deep drama, as menacing gang boss Sister Hua (Elena Kong) coaxes Peipei into carrying more dangerous contraband. But instead of cranking up the tension as the stakes increase, Bai takes a smart, thoughtful approach. She’s less interested in whether Peipei gets caught or not, and more in the shifts in her identity from beta-friend to gang girl. She has a light touch and a precise way of finding the emotion in scenes. It took her a decade after graduating film school to get this film made – it’s worth the wait.