Kramer stated later that the principal actors believed so strongly in the premise that they agreed to act in the project even before seeing the script. Production had been set for January 1967 and ended on May 24, 1967. At age 67, Spencer Tracy was in poor health with heart disease, diabetes, high-blood pressure, respiratory disease, and other ailments. Aware of Tracy's failing health, insurance companies refused to cover him. Kramer and Hepburn put their salaries in escrow so that if he died during the production, filming could be completed with another actor. According to Kramer, "You're never examined for insurance until a few weeks before a picture starts. with all his drinking and ailments, Tracy always qualified for insurance before, so nobody thought it would be a problem in this case. But it was. We couldn't get insurance for Spence. The situation looked desperate. So then we figured out a way of handling it. Kate and I put up our own salaries to compensate for the lack of an insurance company for Spence. And we were allowed to proceed."