I have now finished the second book in the Rebus book series. It was interesting how well-formed Rebus was in this one compared to the first novel. In book one he was one dimensional and you could sense that this book was conceived as a one-off. Rebus has more of a character in the second book, and there is way more police procedure.
I imagine that as a book or television series goes on, the risk would be that in trying not to repeat yourself, you Flanderise your character, or your storylines jump the shark. In the Rebus books, Rebus ages with the books to a certain point, and then the ageing process slows down. This is similar to Michael Connelly’s Bosch character, who is now so old and sick that he appears less and less in Connelly’s novels.