[Spoilers] BBC Press release - series 9

[TygerBright]

I could never in a million years see Malcolm to be a traitor, for whatever reason. Ever.
Nicholas Blake though - always been a ruthless so-and-so. Absolutely possible. And I agree that this whole angle will be wrapped up quickly.. unless - apparently they had to go back and re-visit old eps and 'threads' to make everything fit. What if Nightingale (in different disguises) has been around much longer.. and that Vaughn character and Lucas' past are parts of the puzzle?