Explaining a Movie on Instagram: "Peter Mayhew delivered Chewbacca’s lines in English while filming the original Star Wars trilogy. Behind-the-scenes footage shows him speaking full dialogue inside the suit so Harrison Ford, Carrie Fisher, and the rest of the cast could respond to clear emotional beats and natural timing. Ben Burtt later replaced Mayhew’s on-set performance with the Wookiee vocalizations in post-production, but the actors worked with real spoken lines during shooting."