Throughout the events of Phase 1 of the MCU, one of the biggest connective tissues was Clark Gregg‘s Agent Phil Coulson. The S.H.I.E.L.D. agent helped bring the Avengers together, and when Loki stabbed him in the heart, it looked like one of S.H.I.E.L.D.’s best agents’ time had come to an end.

Then in 2013, only a year after his death, ABC made the decision to pick up the first television show from Marvel that existed within the MCU – one that would focus on the Agents of S.H.I.E.L.D., and a certain fan-favorite character, Agent Coulson. Which, of course, meant they had to find a way to resurrect Coulson. ABC picked up the series with the hope of piggy backing off the success of the movies and giving the network a bonafide success. When Agents of S.H.I.E.L.D. debuted in September of 2013 to over 12 million viewers, they likely thought their hopes were achieved.

However, due to a lackluster story that included milking the mystery behind Coulson’s rejuvenated health while trying to also develop five brand new characters, viewership continued to decline throughout the first season. During the halfway point of the season, there was a major question mark floating around the series and whether or not they would get a chance to further the story. That’s when Captain America: The Winter Soldier came along and gave the show a much needed boost of energy.

The collapse of S.H.I.E.L.D. easily could have ended the series but ABC decided to keep it around for another year. However, as the story and characters continued to improved, audience interest continued to decline. Now, while we wait for season 3 to resume from its winter hiatus, S.H.I.E.L.D. has stayed around 4 million viewers consistently. That is far from the original 12 million viewers that tuned in to the premiere. But the recent season 4 renewal is not a surprise to me.

Season 3 of S.H.I.E.L.D. has taken the series to another level as they continue to explore the effect of the Inhumans and build out the Secret Warriors roster. When the show first began, they were eager to throw a MCU reference any chance they had. Whether it was shameless name drops, or “tie-in” episodes that included them cleaning up the debris in London from Thor: The Dark World. Now, Agents of S.H.I.E.L.D. stands on it’s own within the MCU and is making things happen that will HAVE to be addressed in the larger universe at some point in the future.

The show has taken characters some found annoying in the first season and made them super powered, villainous, and morally complex. Before season 3 started, I wrote an extensive breakdown for returning characters and it’s crazy how much they’ve changed since then. Coulson is a cold blooded killer. May is sympathetic. Daisy is in full control and a leader. Ward has died and been inhabited by Hive… you get the point.

Even as the show struggles to become an elite series in terms of viewership, it has become elite in every other aspect. This is why as of right now, I consider Agents of S.H.I.E.L.D. to be Marvel’s biggest success yet. No one would have thought during season 1 that this show would make it to season 4, with it seeming likely that it will keep continuing after that. The movies are always successful thanks to the Marvel brand and are well received by all, and the Netflix shows have proven to be some of the best entertainment Marvel is putting out these days. Which is all great, but Agents of S.H.I.E.L.D. started off as a question mark and as it took its bumps and bruises, has become an incredibly strong series that Marvel, ABC, and everyone involved should be proud of.

Episode 3×11, “Bouncing Back“, of Agents of S.H.I.E.L.D. will air on Tuesday at 9 p.m. EST on ABC.