But Karloff, ever the professional, continued to work in films. I don't know if he really needed the money to cover his medical expenses or if he did it out of a sense of integrity and professionalism. More likely, he took the work to have something to do rather than sit around and wait for time to run out. Best he go out doing something he loved.
Thus, in the spring of 1968, Boris Karloff made not one last film but four. The films were ISLE OF THE SNAKE PEOPLE, THE INCREDIBLE INVASION, THE FEAR CHAMBER and HOUSE OF EVIL. The films weren't released until 1971, two years after Karloff's death in 1969.
All of the films were co-productions between a small U.S. studio and a modest film studio in Mexico. Karloff was unable to travel so all of his scenes for all four films were shot back-to-back on a small sound stage in Los Angeles. His scenes were directed by Jack Hill. All of the exterior shots and sequences that did not involve Karloff were shot in Mexico. The story goes that a wheelchair and oxygen tank were always on the set, just out of camera range and as soon as a take was completed, Karloff would hurry to the chair and tank for much needed relief. He also suffered from a bad back and many of his scenes were filmed with Karloff seated.
These are not great movies. I recently watched one of them, ISLE OF THE SNAKE PEOPLE and it's pretty bad. It's a shame that one of the greatest horror stars of all time, the legendary Boris Karloff, would make his final screen appearances in such disappointing fare. Still, as always, he gave 100% in his performances. A professional could do no less.