Watch Dexter Season 5 Episode 10 - In The Beginning. Dexter Morgan is back for another episode of action, drama and suspense. In the previous episode, Dexter and Lumen hunted for their new victim but got unfocused by the arrival of a surprised visitor. Lumen and Dexter’s partnership in hunting and killing seems getting deeper each day and as the newest episode of the series is now set to hit your television screens, Dexter and his new partner in crime are about to face a new mission and a brand new victim.