WARNING: The following article contains minor spoilers for recent episodes of Agents of S.H.I.E.L.D.
Agents of S.H.I.E.L.D. was just renewed for another season, and there's plenty of reason for fans to celebrate. As the series heads into its sixth season, the Marvel drama continues to cement itself as one of the best superhero shows on television -- but it certainly didn't start out that way. While it started off a bit rocky, over its five season run the series developed a long-form narrative structure that has put it leagues above its competition. By breaking its season down into "pods," or smaller story arcs, Agents of S.H.I.E.L.D. has changed the name of the game.
When S.H.I.E.L.D. initially debuted on ABC, the series followed a familiar formula. Though it wasn't quite a procedural, it did borrow heavily from this tried-and-true television narrative style in Season 1. As they fought off Hydra and other baddies like Ian Quinn and the Clairvoyant, Phil Coulson and his team searched the globe for 0-8-4s, or "object[s] of unknown origin," every few weeks. This continued through to the first few episodes of Season 2, but that's when the show began to change.
In Season 2, S.H.I.E.L.D. took a far more linear approach to its storytelling. One of the 0-8-4s turned out to be an Inhuman artifact, which led to the discovery of Terrigen, which led the team to meet Daisy's mother Jiaying and her Inhuman commune, which led to a worldwide Terrigen contamination. As with most serialized shows, S.H.I.E.L.D. Season 2 used its 22 episodes to build a straightforward story (with a subplot or two) that reached its climax and conclusion in the finale.
The show continued to evolve in Season 3. In this season, the show gave its story arc a subtitle: "Secret Warriors." In observance of this, S.H.I.E.L.D. dealt with the fallout of Season 2's finale and followed Daisy as she recruited NuHumans to her team. However, the season was much more than its Secret Warriors; it also sent Simmons to another planet, unearthed Hydra's true origin and unleashed an ancient Inhuman with plans to enslave his people. Each narrative wove together, becoming more tightly wound as the season reached its conclusion.
Season 4, however, took a radically different course of action. This year, the season was broken down into pods, each of which had its own subtitle: "Ghost Rider," "LMD" and "Agents of Hydra." Each pod contained a story that had its own beginning, middle and end, like mini-seasons within the larger narrative. By the end, though, it became clear how connected those smaller stories actually were. The finale used aspects introduced into each pod to bring the season home, proving just how vital each smaller story was to the season-long narrative.