Will Chalk

Raksha Bham stands on the back of a pickup truck with a microphone in her hand.

She tells crowds of schoolchildren and young people to raise their voices in peace.

By nightfall, 19 people will have been shot dead in Kathmandu, including 17-year-old Shri Amjad.

Ganga Karki is his mother.

But how did a peaceful Gen Z protest end in bloodshed?

The BBC forensically examined more than 4,000 videos and photos, along with exclusive testimonies, to piece together what happened that day.

According to internal police documents seen by the BBC, permission to use live ammunition was granted at 12.40 on police radio.

These were the exact words used, voiced by an actor.

Less than two hours later, after at least four people are shot dead, Shriyam can be seen in the crowd.

A group of protesters ahead of him pelt the police with stones.

But Shriyam turns away from the violence.

Over the next 48 hours, Parliament, along with hundreds of other buildings, are set alight.

13,000 inmates break free from prison.

Three police officers and at least 50 more Nepalis are dead.

Then the Prime Minister resigns.

Shriyam's mother again.

for them it was just a student who died for us the world we knew has fallen apart an official inquiry into the violence is yet to report its findings no one has been held accountable for these deaths sabina shrestha

Now, hear the words one-eyed cyclops, and you're probably thinking horror or sci-fi film, not important human ancestor.

But a new study suggests our eyes evolved from these creatures, and we share these roots with all other vertebrates.

The BBC science presenter Marnie Chesterton has been looking over the research.