In the ten weeks leading up to the Season 10 premiere of The Walking Dead on Sunday, October 6 at 9/8c, AMC will be revealing information on the new season each week – photos, videos, and never before seen content.

As announced on The Walking Dead panel at San Diego Comic-Con, Thora Birch (American Beauty, Clear and Present Danger, Ghost World, Hocus Pocus) will join the cast as Gamma in the upcoming 10th season.

View Thora Birch as Gamma Now

Gamma is a Whisperer sentry fiercely protective of Alpha. She is a believer and committed to the Whisperers’ way of life.

Today, the network unveiled first-look images of Birch as Gamma.

When Episode 1 of TWD Season 10 premieres, it is now Spring, a few months after the end of Season 9, when our group of survivors dared to cross into Whisperer territory during the harsh winter.

The collected communities, led by Daryl (Norman Reedus), Michonne (Danai Gurira) and Carol (Melissa McBride) are still dealing with the effects of Alpha's (Samantha Morton) horrific display of power, reluctantly respecting the new borderlines being imposed on them, all while organizing themselves into a militia-style fighting force, preparing for a battle that may be unavoidable.

But the Whisperers are a threat unlike any they have ever faced. Backed by a massive horde of the dead, a conflict with the Whisperers is seemingly a fight the survivors cannot win. The question of what to do, and the fear it breeds, will infect the communities and give rise to paranoia, propaganda, secret agendas, and infighting that will test them as both individuals and as a society. Find out what makes Alpha and the Whisperers so dangerous here.

The very idea of whether civilization can survive in a world filled with the dead hangs in the balance.

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