When racial hatred turns to murderous menace . . . First a rocket ship loses its engines on take-off and is destroyed. On board - an important extra-terrestrial visitor. Next someone slams into the sealed vehicle used for transporting aliens around in the lethal atmosphere of Earth. Then the vital controlled environment for the Tau Cetian delegation is sabotaged. Oxygen leaks in, and the aliens are half burnt alive. Even if it means brutal murder,…