A progress report on the fight against cancer. The cancer cell, a tiny pinpoint of life, is the target against which a whole battery of scientific research is levelled. To explain the complexity of the problem, the film traces the growth and multiplication of a single fertilized cell into an adult man, and asks why, after the body has reached maturity, some outlaw cells begin a persistent and subversive growth of their own. The answer may come from any part of the world, as scientists follow every clue that may lead to a solution.