Unlike previous installments in the Star Trek franchise, Deep Space Nine focused on war more than exploration. At the time of its airing, many fans disliked that change. However, it opened up a lot of avenues for the future of the franchise by dealing with darker themes and personal stories that attracted a larger audience. The Federation learned about the Dominion early in the series, but it wasn't until the third season that they discovered how nefarious the Dominion was. Everybody in the Alpha Quadrant saw them as an enemy no different from the ones they faced before. The episode "The Die is Cast" changed everyone's perspective.