Peter Taylor investigates why young British Muslims, born and raised in the UK, end up plotting violence against it. The series opens in the shadow of the failed Christmas Day bombing of a Detroit-bound airliner, using that near-miss to trace how a handful of ordinary young men arrived at the decision to kill. Taylor gets access most reporters do not: face-to-face interviews with people who have flirted with or fully embraced extremist networks, and a look at the forums and online sermons where recruitment now happens without anyone leaving their bedroom. The series treats the internet less as a tool than as an environment, one that connects isolated, angry individuals to a global current of grievance and religious justification for violence. Taylor pushes on the personal histories behind the ideology: alienation, family rupture, a search for belonging that radical preachers and websites are ready to supply. The result is less a security briefing than a study of how a British teenager becomes someone his own country calls a threat.