It is quite an achievement to create a character that the reader likes so much that when the twist comes that reveals they are far from innocent you forgive them.
Yet when you read about it in black and white it seems odd that an old and introverted man with relatively limited social skills can become the hero of the piece.
The problem is that as he is starts to be unravelled the reader is challenged more and more to make up their mind about Castle and to decide whether or not you can still sympathise with him when he is so adept at playing the spying game. he might be doing it for love but people are dying.
More tomorrow...