AMC's The Walking Dead, starring Andrew Lincoln as the venerable Rick Grimes who protects his clan of survivors from the zombie "walkers" who have taken over the rest of the world, wrapped up its Season Two finale Sunday night with "Beside the Dying Fire."

Since Rick killed his best friend / worst enemy, Shane (Jon Bernthal), at the end of last week's episode in a move that was as much about revenge as self-defense, he's had to pull out all the stops in order to keep his little group from dividing and going out on their own. Make no mistake about it — things are changing under the new regime. "If you're staying, this isn't a democracy anymore," Rick told his people.

The real kicker of the finale had to do with the zombie virus itself. It turns out that Dr. Edwin Jenner (Noah Emmerich) from the CDC revealed the secret to Rick in the first part of the season — everyone is already infected with the zombie virus. The only requirement for the illness being activated is to die. People started to figure this out when Randall became a zombie despite not being bitten or scratched. "We're all infected," Rick finally revealed. "At the CDC, Jenner told me. Whatever it is, we all carry it."

And what season finale would be complete without the introduction of a new shadowy character? The mysterious Michonne, played by Treme's Danai Gurira makes her first appearance, looking like she just stepped out of the pages of the original comic book by Robert Kirkman, Tony Moore, and Charlie Adlard. Samurai sword in hand, the hooded Michonne saves Andrea (Laurie Holden) from being cornered and gobbled up by a group of walkers. Two armless zombies in chains mindlessly follow her. The camera zooms in on her face, concealed by the shadow of the hood, and the screen goes to black.

The Walking Dead will start filming for Season Three in May. Along with Gurira as Michonne, David Morrissey will join the cast as the villain, The Governor, and Michael Rooker will return as Merle Dixon, who was left for dead on that rooftop all the way back in Season One.

Watch Andrea's rescue here:

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