The film follows four top song contestants chasing a $5,000 (£3,500) prize while being voted on by the Afghan public via cellphone text messages. Rafi Nabzaada is a Tajik heart-throb, from Mazar-i-Sharif in the North. Handsome, dark and grinning, he could fit into any teen boy band. Lema Sahar is a Pashtun woman from Kandahar - a composed, wary singer beneath her veil and conservative silk garb. Hameed Sakhizada is the ethnic Hazara guy, a classical musician turned pop singer. Setara Hussainzada is a Herati, brassy and brave, uncowed by the mullahs and even a public denunciation by the Herati warlord Ismael Khan. Marking's camera follows Setara on a trip home after she's voted off the stage, right into her family compound on a dusty Herat side street, where it captures a teary, emotional reunion with her family on film - something no male director could have achieved.

Voting is a novel notion in Afghanistan. The Afghans pay to vote for their favourites - the cost-per-call of 10 cents (6p) is serious money for people with an average annual income of $400 (£280). Larger-scale organised political activity also emerged during the song competition. Marking's camera follows the four stars around the country as they "campaign" like politicians. Their fellow ethnics (Tajik, Pashtun or Hazara) line up behind them in the campaigns, but the film shows the stars trying hard to appeal across ethnic lines, like politicians striving to attract the median vote after locking in their base. President Hamid Karzai and his rivals are shuffling the same ethnic cards in the run-up to September's scheduled election.

"One result of Star is that the primary ethnic identifier will become less and less relevant over time" in music and politics, predicts co-producer Saad Mohseni. Samuel Huntington said this was the way it was supposed to work in his 1968 classic, Political Order in Changing Societies, but Huntington probably didn't have a pop song contest in mind.