CUs and MSs of doctors being interviewed at Princess Margaret Hospital including RR Clash, Louis Seminovitch, in charge of microbiology, Arthur Axelrad, in charge of immunogenetics and psychology, Arthur Hand, head of biological research, Dr Cunningham, explaining function of betatron, Dr Alit, explaining operation of automatic brain scanner, Dr Altt and Cedelund, explaining function of another machine, Dr Cedelund, Dr Peters, a woman, Dr Warwick speaking to the camera, Dr Ash speaking to the camera, Dr Warwick speaking to the camera, Dr Ash speaking to the camera, Dr Whitman explaining chromosome theory on a blackboard in Van de Graf generator room, Dr Ryder explaining function of betatron in relation to patient.