A premiere Friday for the sixth season of AMC's "The Walking Dead" at Madison Square Garden was so big and orchestrated, its stars attended a rehearsal that afternoon to prepare.

The event, which awarded fans with tickets via giveaways and sweepstakes, screened the season premiere and then held a panel with 18 cast members.

"It's a giant arena with 18,000 seats and Led Zeppelin's played here, I think Muhammad Ali fought here, so it's really a special venue," actor Austin Nichols said. "I'm honored to be here."

The red carpet itself was moved inside at the last minute due to rain and wind, but that didn't keep away the fans, many who dressed as zombies, or "walkers," as they're called on the series.

"The Walking Dead" is about people trying to survive in a zombie apocalypse. Over time, it's evolved from being about people trying to escape the undead to people trying to outlast others as civilization and order has crumbled around them.

"It was always going to be about how an environment changes people," star Andrew Lincoln said. "Some turn to the dark and some try and keep hope alive."

Click here to subscribe to FOX411’s YouTube channel

Lincoln said that in the sixth season, however, the zombies make a comeback: "The zombies are very much back in the foreground."

"Emotionally, physically, everything is absolutely relentless," added actor Ross Marquand. "They're dealing with the threats from all these different tribal factions that are trying to kill them. We're dealing with more and more zombies than ever before. It's just incredible."

"The Walking Dead" is one of the most watched shows on television and has a global fan base.

"I'm from Zimbabwe," actress Danai Gurira said. "People watch it there. I've been stopped on the streets of Zimbabwe for being Michonne so, it doesn't get more far away than that, you know? It's really exciting to see that my work in the United States is embraced by my other home that's so far away."

The sixth season of "The Walking Dead" premieres Sunday at 9 p.m. Eastern.