BONUS CONTENT: From the network that brought you Mad Men, and The Walking Dead, comes an addictive crime thriller with crushing twists. Get an exclusive peek at the script for The Killing, AMC’s newest original series, which tracks the murder of a Seattle teenager and the gripping investigation it sparks. April 3 at 9/8c, only on AMC.WHO DO YOU LOVE?   One question, a split-second decision, and Brian Darby lies dead on the kitchen floor. His wife, state police trooper Tessa Leoni, claims to have shot him in self-defense, and bears the bruises to back up her tale. For veteran detective D. D. Warren it should be an open-and-shut case. But where is their six-year-old daughter?   AND HOW FAR WOULD YOU GO . . .   As the homicide investigation ratchets into a frantic statewide search for a missing child, D.