For those who have billed this as an answer to Mission Impossible or The Bourne series... they are setting this up for a fall. It is not. But I don't think that has ever been the intention.
If you cut all of the stereotypical American patriotism and bravado, add a more intelligent approach (one too intricate for that US market). You're about there.
Although you won't be seeing Kit Harrington drop forty feet on a rope, catch a bead of sweat in slow motion, before it hits the floor sensors. You will see a nod to Tinker Tailor Soldier Spy, and the internal corruption of the British Secret Service. Its well put together, takes you one way and then spins you 180.
Its a stimulating spy film, which engages the audience to actually have a think while watching it. As good as the M.I and Bourne franchises are, this is all together different. I have never seen Spooks on BBC, but this has pushed me to take a look at what I've been missing out on.
I unfairly went in with a low expectation of this film, and was pleasantly surprised.
A good watch, and one I wouldn't turn anyone away from. Though it does make you think... what am I missing out on, what do the public not find out about, how good are the MI5?