One thing that has always fascinated me about Babylon 5 is all of the different races and how they related to one another. You've got Humans and Minbari who fought a terrible war in which the Human race is almost destroyed, then like 12 or so years later they become allies. You have the Narns and Centauri almost constantly at war. You have the Vorlons using everyone else to do their work, only seeming to form an alliance with the Minbari when they were really using them. Earth signs a non-agression treaty with the Centauri, but the Humans on B5 really support the Narns. Then there is the Centauri alliance with the Shadows and their wars against the League Worlds, who turn to the Humans and Minbari for help. There are just so many different fascinating ways that these races relate to one another. I could sit and watch B5 for hours just taking all of that stuff in.