The suspense is there in the first three episodes, then it kind of become obvious where the show is taking us. However, the biggest problem is that most things don't add up. For example, something akin to a terrorist cult, which the state already knows about, is the priority of a single police officer who has to resolve it for his own mental welfare (ironically the Home Minister lets him) . That will make sense in some small town far away from centre. Not in a big city like London.