He played the lead character role, a superhero, on the Saturday morning television series "Shazam!" and performed his own stunts. However, he was dismissed from the cast of "Shazam!" two installments into the second season and replaced in the role by John Davey. Bostwick had not shown up for a day's shooting, and the producers, Louis Scheimer and Norman Prescott, accused him of holding out for a higher salary. Bostwick explained that he had sustained an injury during the previous day's filming and had gone to seek medical treatment. In an interview, he stated, "I was at the doctor's office having my face and eye examined for an injury that I incurred doing a stunt on the previous day (during the filming of a flying takeoff sequence where the stunt boxes hadn't been reset properly)." He successfully litigated against Filmation Associates, which was forced to pay him for the remainder of his contract, plus residuals, including the entire second season.