For months and months, the comet was morely a ball of greenish mist, neastled among the stars, gleaming over the night. In time, people got used to it, although some called inthe Star Judgment, and predicted that the end of world was near.

There was no doubt in the minds of scientists, however, that the paths of the Earth and the comet were soon to cross, but no one could predict the result.

When ot finally struck, the effect was astounding - for at the touch of the comet's strange gas, a catalytic change passed round the globe, and the world was transformed...