Moll is best known for portraying the towering but sweet-tempered bailiff Bull Shannon on the sitcom Night Court from1984 to 1992. Two actresses who played Bull's female friends also later appeared in the DCAU, Murphy Cross and Denny Dillon. Bull's mother appeared in one episode, played by Paddi Edwards; another memorable guest appearance was made by Arte Johnson as Gregor, a Russian emigre who treats Bull as a surrogate son. Moll also portrayed the undead villain of the movie House (acting alongside William Katt) and has performed extensive voice work.