Professional curmudgeon Leo McKern stars as taciturn Professor Bowles-Ottery, who grows tired of seeing the world overrun with useless people. Through experiments in his lab, he develops a gas that will take care of the problem -- permanently. But it's not all bad news for the victims of his gas: they will die amid uncontrollable laughter. Janet Munro, Duncan Macrae and Maxine Audley co-star in this pitch-black British satire.