Yvette Nicole Brown just had a super sneaky Walking Dead cameo

Fans of The Walking Dead may have been a bit confused when they got to the end of Sunday's "Outpost 22" episode and saw the words "Special appearance by Yvette Nicole Brown" pop up on screen… especially considering Yvette Nicole Brown did not appear to appear on screen at any point during the episode. So what gives?

While the star of Community, Big Shot, and 10 million other series, movies, and talk shows over the past two decades may not have shown her face, she provided her voice, delivering some key information for the climactic scene in the episode.

Trying to find their friends and the ultimate destination of a Commonwealth train they hijacked, Rosita (Christian Serratos) and company attempt to contact the mysterious Outpost 22 over the radio, pretending to be a lost Commonwealth soldier. While only silence is returned at first, finally a voice answers giving directions to the location of the outpost — a location that turns out to be the heroes' old home of Alexandria, now taken over and controlled by the Commonwealth.

Amy Sussman/Getty Yvette Nicole Brown at Comic-Con

The voice explains, "We have a convoy coming in for priority reprocessing," as we see Negan (Jeffrey Dean Morgan), Ezekiel (Khary Payton), and Kelly (Angel Theory) on a bus entering through the gate. "Word is that most of the processees used to live here before the Commonwealth claimed the territory and turned it into an outpost back when it was still called Alexandria." The Outpost 22 voice finishes off by telling the disguised Rosita to "watch out for any hostiles on the road. If you have to engage, shoot to kill."

So how did Brown — a certified Walking Dead superfan who has appeared (with her trusty notebook of questions, comments, and theories about the show) numerous times as both a guest and guest host on Talking Dead — end up on the receiving end of that radio? The star herself explains.

"I was super sad that the show was ending, and told Angela Kang and Scott Gimple that I wished I could be a part of the show in some way before they wrapped," Brown tells EW. "Traveling to Atlanta to perhaps be a walker wasn't possible, so they came up with the idea of me being a part of the show via voiceover, and I couldn't have been more excited to do that. I didn't know if I'd be credited, and didn't know if my fellow fans would be able to tell it was me if I wasn't. I'm surprised that quite a few knew it was me immediately and am humbled that I was credited — I would've been happy being an eternal Easter egg on my favorite show."

Jordin Althaus/AMC Yvette Nicole Brown and Gale Ann Hurd on 'Talking Dead'

And The Walking Dead creative team was happy to have their biggest celebrity fan join the family. "Yvette is a great friend of the family," says showrunner Kang. "She is such a great supporter. She's an amazing actor in her own right, and she was open to maybe doing something for us."

But getting on The Walking Dead is not as easy as that, especially if you have a famous face. "Without getting into it, through the years there have been various celebrities who've been like, 'I'd be interested in doing a cameo on the show or being walker on the show,'" notes Kang. "But sometimes that gets distracting in a show like this. It works better for other kinds of shows. But in the case of an ADR, it's just a voice that's coming over a radio, and she's a great voice actress. She does that as part of her portfolio of acting work."

The fact that the radio exchange is a meaty one made it the perfect part for Brown. "I knew that I needed a long ADR for this," says Kang. "And I was like, "Oh, I'm not going to throw her one line. I'm going to give her a chunk, because I need somebody really good to do it. She was gracious enough to come in and record this for us, and it was delightful. It was great to see her, and it was great to have her as part of the show."

Now, the only question that remains is… what did the Talking Dead guest turned Walking Dead voice actor write in her notebook about the appearance?

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