After performing again in "Harvey" at the Prince of Wales Theatre in London in 1975, Stewart returned to films with a major supporting role in John Wayne's final film, "The Shootist" (1976), playing a doctor giving Wayne's gunfighter a terminal cancer diagnosis. By this time, Stewart had a hearing impairment, which affected his ability to hear his cues and led to him repeatedly flubbing his lines; his vanity would not allow him to admit this or to wear a hearing aid. Stewart was offered the role of Howard Beale in "Network" (1976), but refused it due to its explicit language. Instead, he appeared in supporting roles in the disaster film "Airport '77" (1977), the remake "The Big Sleep" (1978), and the family film "The Magic of Lassie" (1978). Despite mixed reviews, "Airport '77" was a box-office success, but the two other films were commercial and critical failures. Harry Haun of "New York Daily News" wrote in his review of "The Big Sleep" that it was "really sad to see James Stewart struggle so earnestly with material that just isn't there." Stewart's final live-action feature film was the critically panned Japanese film "The Green Horizon" (1980), directed by Susumu Hani. Stewart took the role because the film promoted wildlife conservation and allowed his family to travel with him to Kenya.