Boreanaz hinted that while it is unlikely that Booth and Brennen will move past the kiss they shared in season 3, they may become physical in some upcomming fantasy scenes. “Obviously this is the fourth season and we have to put the characters in a position where they can become physical,” he said. “Season four will be a bit fantasy driven; it will be a bit film noir. We are going to stretch the boundaries of the characters and there will be some female characters introduced who will cause some friction.”