Yeonmi Park escaped North Korea in 2008. She was only 15 at the time. It came after her father had been imprisoned and tortured for three years, and she'd witnessed atrocities such as watching her best friend's mum executed for watching South Korean DVDs.
Park and her parents fled to China but after her father died, she and her mother escaped to South Korea. That had its own struggles – her mum had been by local smugglers in China, and then when they crossed through Mongolia, mum and daughter had to threaten suicide to be allowed through to South Korea. Her story is remarkable and you can read it in full in this brilliant interview which first appeared in The Telegraph's Saturday magazine.
Now Park is 21, and she is studying criminal justice at Dongguk University. She's also a regular guest on South Korean television programmes and has become something of a celebrity, known for speaking out against the situation in North Korea.
She has a strong presence on social media, using Facebook, Twitter, Skype and WeChat to talk about the human rights crisis in North Korea to thousands of people. YouTube videos, showing her giving talks and appearing on TV shows, have hundreds and thousands of views.
Her activism has put her on Kim Jong-un's radar, and she has been warned by a South Korean official that her name has been added to a 'target list' of outspoken defectors that Kim wants to eliminate. But it has not put her off – instead it encourages her.
"I crossed the Gobi. I lost my father. But I am still not free. They still have power over me. They still try to control me. Until I can be really free, I will keep going," she said.