Following the mind-staggering nuclear explosion which has sent the moon and its research station, Alpha, deep into space, Commander Koenig and his dedicated group of scientists have kept the base going and survived crisis after crisis.

Now a huge, mysterious object crashes into the moon a few miles from the research base. A search party goes out to investigate and almost at once there starts a series of terrifying adventures which look like putting an end to the moon base's incredible odyssey.

First original novel in the series.

Released in the U.K. in 1976 and 2002 and in the U.S. in 1976.