 Production of the episode began months in advance according to the episode 's writer Steve Callaghan . " We 're actually working over a year ahead of time , " Callaghan says in an interview with Hollywood.com. He added " We work so far ahead I can even tell you the finale [ ... ] the finale is a really cool episode called ' Roads to Vegas . ' It 's like a road show and Stewie and Brian teleport themselves to Las Vegas , but in the process [ they ] unknowingly create a duplicate of one another . " In an interview with The Hollywood Reporter , Callaghan recalled the scene in the episode where Brian and Stewie consider joint suicide the most difficult scene for him to write in 2012 . 
