Matt Charman should have stopped with 'Bridge of spies'. This is a not very original idea, and simply overwritten and implausible. Not even Suranne Jones or Martin McCann, (who is brilliant in Blue Lights, BBC) can save this drama from becoming an Eton mess. If you want to save 4.5 hours to do something productive, don't watch this.
Had to add an extra comment after seeing some 4/5 star reviews, did you fall asleep whilst watching. Seriously! If you make it to the scene where the General is found out, lol, and he confronts the PM, I can't be the only one who expects Tom Cruise and Jack Nicholson to spring out! Surely borders on plagiarism??