Christopher Reeve later made even higher gains for "Superman III" (1983), though for "" (1987), he decided it would be healthier to focus more on cardiovascular workouts. One of the reasons Reeve could not work out as much for "" was an emergency appendectomy he had in June 1986. Reeve was never a Superman or comic book fan, though he had watched "Adventures of Superman" starring George Reeves. Reeve found the role offered a suitable challenge because it was a dual role. He said, "there must be some difference stylistically between Clark and Superman. Otherwise, you just have a pair of glasses
Christopher Reeve standing in for a character." On the commentary track for the director's edition of "", creative consultant Tom Mankiewicz spoke of how Reeve had talked to him about playing Superman and then playing Clark Kent. Mankiewicz then corrected Reeve, telling him that he was always, "always" playing Superman and that when he was Clark Kent, he was "playing Superman who was playing Clark Kent." Mankiewicz described it to Reeve as a role within the role. The film grossed $300,218,018 worldwide (unadjusted for inflation). Reeve received positive reviews for his performance: Christopher Reeve also guest starred in "Smallville", the successful American