What happened to DCI Peters?
He was there at the end of season 5, in the episode where Barnard dies. As I recall, he had several scenes with Mullet and was a pretty big part of the storyline about Mullet's "downsizing" the police force. But in season 6 and onwards he is gone.
Was it ever mentioned what became of him? I liked his more relaxed style as a boss to Frost, as opposed to the strained at best relationship between Frost and Mullet.