Irfan Khan/Getty ImagesSam Haskell IV, the son of a retired Hollywood agent, pleaded not guilty on Friday to the gruesome killing and dismembering of his wife and in-laws in Los Angeles. Haskell appeared in court in suicide prevention clothing, shirtless and handcuffed, and has been held without bail since the discovery in November of his wife’s dismembered torso in a strip mall dumpster. Shortly before the discovery, he allegedly attempted to hire workers to dump of his wife’s body parts, unsuc