"They say truth brings light...It's the lies that live in darkness." Everyone's favorite serial killer is back this fall when Dexter Season 7 premieres on September 30th with Episode 7.01: Are You...?, only on Showtime. We have the second trailer for Dexter's impending return, which hints at Debra (Jennifer Carpenter) finally learning the truth about her brother's (Michael C. Hall) wicked pastime. Watch as the truth comes bubbling to the surface.