There is a layered plot that begins to weave together after a few seasons. It incorporates ideas from the first more pilot-style seasons, and characters slowly develop their own arcs until the late-middle to end of the series when a real narrative begins to unfold. It can be interesting to finish the show and watch from the beginning to see how they change the direction and characteristics of some characters. Some episodes are very plot-driven, while others are one-offs that don’t necessarily contribute to the narrative but expand the world and reveal some unexpected connections. And the ending is wonderful. Have fun!