If you aren't caught up on The Walking Dead, be warned: This review discusses plot points from the seventh season.

What kind of Walking Dead will we see this season? Considering what the show's producers put fans through last season, it's a fair question.

Last fall, the show's seventh season started with the deaths of two beloved characters, including Glenn Rhee, a plucky guy who had been on the show since its second episode. The action last year centered on the man who killed those characters with a barbed wire-wrapped baseball bat — Jeffrey Dean Morgan's swaggering, overtalking supervillain Negan. It was bit of a gamble, traumatizing a loyal audience while completely re-calibrating one of the most popular shows on television.

We spent long episodes last season getting to know new characters and communities who were trying to survive the zombie apocalypse while seething under the capricious, brutal rule of Negan's sprawling gang, the Saviors. Negan was working overtime to break our hero, Rick Grimes, and his supporters, a group of survivors who had defeated cannibals and worse. Ratings dipped as some fans backed away.

But on Sunday the show marks an important landmark: its 100th episode and the start of its eighth season. So it makes sense that the first episode is a return to form, of sorts. Andrew Lincoln's intense hero, Rick, and his band of survivors are implementing a complex plan to topple Negan and win back control of their communities. They aren't passive victims anymore; they're active and fighting back. It's the way longtime fans are used to seeing them, and it feels good.

In true Walking Dead style, Sunday's episode isn't exactly told in a direct narrative. Instead, the action jumps around in time. We move from Rick and his allies preparing for their attack, to adrenaline-pumping clashes as they carry it out, to a future in which Rick has an almost Santa Claus-level white beard and a noticeable limp. Despite all the shooting, shouting and action, much of this episode feels like table setting — events mostly designed to maneuver characters and situations into certain positions to enable a greater story later.

It's tough to believe The Walking Dead has lasted this long, remaining the most-watched TV show by 18- to 49-year-old viewers for five seasons running. Originally developed as a graphic novel, the show picks up where most zombie movies end: at the point where animated, flesh-eating corpses have spread across the world and threaten to end human civilization.

Some have seen the show as an allegory for the fear of outsiders that fuels anti-immigrant or anti-refugee sentiments. But I've always felt the zombies in The Walking Dead were more like a natural disaster; a plague that sweeps away all the institutions we rely on in modern society. Faced with that challenge, what kind of person do you become? Can you survive the brutality of this new world and keep your humanity intact? And are the zombies — or "walkers," as they're called in the world of The Walking Dead — the biggest threat, or are other people? Seven years in, the show is still exploring those questions: Sunday's episode has Rick leading a group of not-so-thinly-veiled avatars for a humane post-apocalyptic civilization as they try to outfox a character who often seems like the Devil personified.

But here's one thing I haven't understood in recent seasons: What's happened to Michonne, played by Danai Gurira? She does very little in Sunday's episode, but at one point she was among the show's strongest female characters, adept at wielding a huge, Japanese sword and surviving in a world filled with flesh-eating zombies and even worse people. As she became more humanized and emotionally open — kindling a romance with our hero, Rick, and becoming something of a mentor to his son, Carl — she's been featured less and given less agency. Even as other female characters have grown more independent — especially abused wife turned warrior Carol — Michonne seems to have faded into the background, as if she couldn't be part of a loving, healthy relationship and still have her own independent story.

By now, AMC has built The Walking Dead into a franchise (an after show, a spinoff series, merchandising) but there's been some trouble behind the scenes. Producers filed a lawsuit against AMC alleging they had been shortchanged on profits; and stuntman John Bernecker, whose name is flashed in tribute at the end of Sunday's episode, died this summer after he fell during production.

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