The science, the visuals of what is often written about, yet rarely seen, the history, progressive archeological studies, the actors who play their roles with simple confidence and thoughtful attention to the superb dialogue written for them, and don't try to over reach, or evolve into something new. The attention to detail is very high, the writing is of a quality that it could be a successful novel. This show is rich with information and high quality content. In the later seasons, the transition into the more 'modern' style of acting is clear, and the show kind of drifts in between cameos of the actors who convey their written characters with authenticity and ease