Question: What actor had varying roles in twenty episodes of CBS's "Gunsmoke" with the actor who was best known  for portraying Marshal Matt Dillon for 20 years?
Sentence (from "Gregg Palmer"): He appeared from 1960-1975 in varying roles in twenty episodes of CBS's "Gunsmoke" with James Arness, thirteen segments of the syndicated "Death Valley Days", and nine episodes of NBC's "The Virginian" starring James Drury in the title role.
Relevant evidence: No