On strike at 8,848 metres: Sherpa and the story of an Everest revolution

Jennifer Peedom set out to make a documentary about the untold role the Sherpas play in helping wealthy western climbers conquer Mount Everest, but when an avalanche hit during her shoot, she ended up with an even bigger story

On 18 April 2014, a 14,000-tonne block of ice slid down the southern face of Mount Everest, killing 16 people. It was the mountain's deadliest day, until just over a year later, when 22 died in the aftermath of the Nepalese earthquake.

Thirteen of the men who died in 2014 were Sherpa, an indigenous ethnic group famed for their ability to withstand high altitudes. They had been finding their way through the Khumbu Icefall, one of Everest's most dangerous passes. When the avalanche hit they were fixing a route so that tourists - some paying up to $75,000 to climb the world's highest peak - could fulfil a dream.