Jejoen Bontinck, then a Belgian teenager, became a key prosecution witness in one of Europe’s biggest terrorist trials after he returned from the war in Syria. Bontinck gave evidence against his former friends in the Islamist group Sharia4Belgium, who he claims brainwashed him.
Now at 25, he’s trying to build a new life as a musician under the name Ready4Jerri.
He gave his first interview since the trial to the BBC's Brussels correspondent Nick Beake. In Syria Bontinck spent time in a cell with western journalists including American James Foley, who was murdered, and Briton John Cantlie, who is still missing.
The video is produced by Xavier Vanpevenaege and Bruno Boelpaep.
Follow the link to watch the interview on the BBC website.