We know that Dexter was born in blood — but what about that army green shirt he's been wearing since the pilot? What's the shirt's origin story? With Dexter beginning its eighth and final season on Sunday, we rang up the show's costume designer, Kathleen Felix-Hager, to find out. "The thought behind it was that he has his sort of everyday, lab-geek persona at work," she says. "He wears bright colors and these poppy ice-cream linen shirts and khaki pants. But then when he’s the serial killer, when he puts on the stalking shirt and the cargos, it’s sort of a darker Dexter." A darker, sexier Dexter. Here's what else we learned about his kill clothes. (Plus: Michael C. Hall gets sentimental over footwear.)1. The army green shirt, commonly referred to as Dexter's kill shirt, is actually called his stalking outfit, according to the scripts. "There are two...