In the latter half of the 1960s, Boris Karloff owed legendary exploitation film producer Roger Corman two days of work. Karloff was 81 years old, only had one functional lung and, when the cameras weren’t rolling, was mostly confined to a wheelchair, an oxygen mask strapped to his face. Even with his best days behind him, he was still Boris Karloff, the man behind the makeup of some of the greatest movie monsters to ever grace the screen.