Inseminoid

Man had landed on the planet before: a fruitless, expensive fiasco of an expedition. Then, fifty years later a smaller but disastrous landing had left two men horribly and unexplainedly dead.

Now a third attempt had so far found nothing but a silent, lifeless world. Until they broke open the underground chamber and discovered in the most vile way imaginable that the planet was not quite dead. That a sleeping life had been waiting for millennia, needing only a chance to breed before escaping to spread like a foul, devouring disease into the lifeblood of the universe.

And to breed it needed the bodies of those who had disturbed it.