Up until this episode, Agents of S.H.I.E.L.D. hadn’t yet found their own voice. The characters and plot were still heavily reliant on the timeline of the Marvel Cinematic Universe, and the relationships developing between the main characters aboard “The Bus” seemed either too shallow or too slow-paced. But with “FZZT,” we started to glean histories that deepened the way we view these characters and how they value each other in turn.