Not All Dogs Go to Heaven "American Dad!" character, Avery Bullock in "Lois Kills Stewie" (season 6, episode 5), and his "Star Trek: The Next Generation" character Captain Jean-Luc Picard in "Peter's Got Woods" (season 4, episode 11); Jonathan Frakes, Michael Dorn and Marina Sirtis also appeared in "Peter's Got Woods" as their respective "Star Trek: The Next Generation" characters William Riker, Worf, and Counsellor Deanna Troi. "Not All Dogs Go to Heaven" features the entire original cast of "Star Trek: The Next Generation": Stewart as Captain Picard; Frakes as Riker; Gates McFadden as Doctor Beverly Crusher; Brent Spiner as Lieutenant Commander Data; Dorn as Worf;
Brent Spiner films. As a main character, he appeared in all but one of the series' 178 episodes; he was not in the episode "". He reprised his role in the spin-off films "Star Trek Generations" (1994), "" (1996), "" (1998), and "" (2002). Although billed as the final "Trek" movie for the "TNG" cast, the ambiguous ending of "" suggested a possible avenue for the return of Data. However, Spiner opined that he was too old to continue playing the part, as Data does not age, whereas Spiner had already aged considerably during the years in which he played the role.