Chloe Hadjimatheou tells the astonishing story of a group of young men from Raqqa in Syria who chose to resist the so-called Islamic State, which occupied their city in 2014 and made it the capital of their "Caliphate". These extraordinary activists have risked everything to oppose IS; several have been killed, or had family members murdered. IS has put a bounty on the resistance leaders' heads. But the group continues its work, under the banner 'Raqqa Is Being Slaughtered Silently'. Chloe meets the group's founders, some of whom are now organising activists in Raqqa from the relative safety of other countries.