In past months, dozens of convicted terrorists have been released in the UK, including onto the same London streets. Seldom since 9/11 has al Qaeda, though weakened, had such an opportunity to create carnage on the global stage. At the same time a no-holds barred fight for security is under way. It is unorthodox, but British officials say it is working, producing results which have never been seen before - and at its epicenter is a veteran Muslim cagefighter.
Over the last six months Usman Raja gave CNN's Nic Robertson and CNN terrorism analyst Paul Cruickshank exclusive access to his pioneering efforts; speaking for the first time about his work with former terrorists.
Read their phenomenal reporting:
PART 1: Cagefighter 'cures' terrorists
For CNN International viewers, watch the inspiring "Caging Terror" documentary Saturday at 9.30a.m., 7p.m. and 6.30p.m. GMT and Sunday at 2.30p.m. GMT.