"4,722 Hours" was touted as a monumental episode for Agents of S.H.I.E.L.D., and it was, but not just for the obvious reasons, like the fact we traveled to an alien planet in a different solar system where a mysterious creature (Death?) killed everyone who traveled there. It was also the episode in which we finally learned the detailed truth about what happened to Simmons on that planet and we experienced it with her, not through a retelling of her story or through the use of flashbacks. The entire episode was one long flashback, yes, but it wasn't presented that way, and that set up allowed us to experience the events alongside Simmons. It immersed viewers in her emotional journey, but more importantly, it also helped sell her relationship with Will.