P and D entered into a lease contract on September 3, 1941, for a neon sign. P retained the title to the neon signs and tubing which it installed and maintained on the exterior of D's 'drive-in' restaurant. WWII happened, and on August 5, 1942, the federal government prohibited the illumination of all outside neon or lighting equipment between the hours of sunset and sunrise. D asked P to remove the signs and to terminate the contract. P refused. D stopped payments on September 1, 1942. P sued, and the court found for D under commercial frustration, thus excusing both parties from performance. P appealed.