A fearsome thing is a thing you're afraid of--and it has nothing whatever to do with whether others are afraid, nor with whether it is in fact dangerous. It's your view of the matter that counts!
In exchange for the promise of an almost limitless fuel, earth agrees to allow the alien Grdnzth people to gather on earth for transit to a planet as their is going to be destroyed. The Grdnzth are ugly, looking rather like reptiles. They also pop in anywhere, anytime unannounced. It's the job of PR men Pete Greenwood and Tommy Heinz to get the public to accept the Grdnzth and the inconvenience...
An expedition team of scientists is exploring the planet Mercury. The constant rumblings of earthquakes and wind have shaken their ship, the Albireo. A small explorative party departs on tractors. It's then when the volcanic reaction starts. And it looks like the end of the team unless man's intelligence can beat the malevolent nature of a fiery planet!