[spoilers] Lucas. Just Lucas.

[theeyeshaveit]

What disappoints so much is not what they did with Lucas in making him act like a rogue agent, but the why.

We could have had 90% of what we got, someone coming back on the scene to push his buttons, him doing everything he did, us coming up with the same theories like, is he undercover, is he reprogrammed, is he working for the Russians, and it could have played out pretty much the same. They had plenty of reasons why he could have behaved this way because of events in his MI5 past, which would not have totally destroyed and demeaned his character as did the option they went with and it was not even believable.