If you’re heading out to the Theater District on Saturday, watch out for the zombies. No, really. “Every year, we run into people in their tuxedos and [formal dresses] leaving the symphony or the theater. They never know quite what to make of us,” laughs Darren Tompkins, organizer of the 2013 Houston Zombie Walk and Halloween Party. “Sometimes they just stop and stare, sometimes they join in and sometimes they run away.” Now in its third year, the Zombie Walk will have a Texas Rockabilly theme for 2013. Most participants dress up (“we get everything from last-minute costumes to elaborate, professionally made cosplay outfits”), but it’s not required (“if you just want to come watch, that’s fine”). Tompkins says donated costumes and volunteer makeup artists will be on hand if anyone changes his or her mind after arriving at the party. In addition to the zombie walk, this year’s party features -music by the Reverend Horton Heat, lots of family activities, food and adult beverages. “You’re going to see a monster crowd,” quips Tompkins.