Agents of S.H.I.E.L.D., on ABC
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Caution: potential spoilers

Season Seven
This is the final season. I don't want to reveal too much about it. I will say that our heroes spend basically the whole season in different eras of the 20th century, always trying to stop the Chronicoms from altering the timeline to eliminate SHIELD. The Chronicoms are led by a woman named Sibyl, who can see countless possible futures using a device called the Time Stream, to calculate their odds of success depending on their own actions and those of the SHIELD agents. And despite SHIELD's best efforts, the timeline changes in numerous ways, even if they manage to stop the Chronicoms from completely winning in their own efforts. And early on, Agent Daniel Sousa (from Agent Carter) gets plucked out of his own time and joins the crew of Zephyr One in their travels through time. And in the latter part of the season, Nathaniel Malick becomes a major enemy, who works with the Chronicoms for his own reasons. Also, Daisy meets her half sister, Kora, who has a powerful but unstable Inhuman ability. She had died before Daisy was born in the original timeline, but in the new timeline she survives, and begins working with Nathaniel. Another very impotant thing to note about the season is that Fitz isn't seen until the 2-part series finale, and the Chronicoms desperately wanted to find him, as Sibyl had seen that he is the key to their ultimate defeat by SHIELD, in various possible futures. Only Simmons and Enoch had known where Fitz was, but Simmons herself spends most of the season not knowing, because of a brain implant that blocked her memories, so that the Chronicoms wouldn't be able to get that information from her.

Well, I'm leaving out tons of details, but I hope I haven't forgotten anything too important. Needless to say, the good guys win in the end, in spectacular fashion. And there's a very nice scene set one year later, to close out the story. The way it all ends is... cool.