Actor Ray Liotta has been cast to voice Moe the bartender's father, Morty Szyslak, for an upcoming episode of 'The Simpsons'. The episode, which will reveal more of Moe's backstory than viewers have even seen before, is set to air April 15. A 20th Century Fox spokesperson tells TheWrap that Liotta's Morty is described as a more cunning, evil version of Moe.