The terrorist bombings in London in 2005 were shcokcing because, thankfully, such events were (and still are) unusual. This series gives us first hand accounts of the survivors, and of the subsequent police investigation to track down the perpetrators. The latter caught some of the bombers (the others had died in their own attacks), but also killed a wholly innocent man (and, inexcusibly, the police told untruths when first speaking of this in public). As a documentary, this programme is arguably a little slow; the story could probably have been told at three-quarters length - but it's a compelling story nonetheless. I would have liked to know more about the bombers' justifications: I very much dount they would have convinced me, but precisely because their actions seem so inexplicable (terrible and yet the opposite of self-interested); but I guess giving platforms to imprisoned terrorists was not the aim of the series. It still does its job of reminded us of the thin thread by which civilisation sometimes seems to hang.