Suit...

Yes. If youve seen the previous film he was gravely injured, but does in fact survive according to the novels.

In one of the movies Suit' got shot in the head and was in a coma. In the next movie (Sea Change) he wakes up from the coma, but is a bit different. As Jesse Stone put it "Suit isn't quite in the same duck with the rest of the pond." He's a bit forgetful in regards to long term memory. He's not handicapped by it in anyway, he just lost some memory from the trauma. He actually comes back as more like Jesse. He gets those "coply feelings" Jesse gets. He becomes more of a sidekick to Jesse and someone Jesse respects and knows if Suit' wasn't in a small town police force...would become a detective quickly.

At any rate I am sure he'll be back. He's a very well respected character.