When Uli Sigg began looking for contemporary art in China nearly three decades ago, he was surprised nobody was collecting it systematically. So he decided to do it himself.

The Chinese Lives of Uli Sigg, a documentary to be screened alongside 44 others at this month's Beirut Art Film Festival, tells how Sigg became the world's largest collector of Chinese contemporary art, gathering more than 2,000 pieces. In 2012, he donated around 1,400 of them to the M+ Museum for Visual Design, set to open in Hong Kong in 2019.

"I thought it's very weird - the biggest culture space in the world and nobody's paying attention to the contemporary artists," said the Swiss diplomat and businessman during a visit to Lebanon.