If you were a fan of Tennant before Doctor Who and one of Morrisey before The Walking Dead, then this episode is a dream. As an adversarial pair in Black Pool, these two actors chewed up the scenery and gave an audience something spectacular. In this episode they truly work off that chemistry as eventual allies, and the performance is one based on familiarity and trust. That permeates the episode. RTD gives enough cheek (Rosetta), sentiment (the son) and emotional foreshadowing (the next Doctor) to create a fully satisfying episode. To look back and see The Governor in such a sympathetic role speaks volumes to his talent.As to Tennant - well, if you're a fan, you know his work here, there, and recently on Broad Church speaks for itself. Wonderful episode.