'The Walking Dead': 7.3 million watch season 2 premiere

Zombies have done it -- crossed over to a mainstream audience, that is. Sunday's (Oct. 16) season 2 premiere of "The Walking Dead" drew 7.3 million viewers, breaking records in two key demographics -- 4.8 million adults 18-49 and 4.2 million adults 25-54.

According to an AMC press release, the numbers are up more than 30 percent over 2010's season 1 debut.

To put it in perspective, "Mad Men's" fourth season premiere -- in July 2010 -- drew 2.5 million viewers, while 2.6 million tuned in to "Breaking Bad's" July season 4 debut.

"'The Walking Dead' is one of those rare television programs that reaches both a core genre fan as well as broad audiences simply looking for a great, character-based story," said AMC president Charlie Collier.

Season 1 had an average of 3.5 million viewers per episode.