What if our most treasured verities were in fact wrong?

To be selected for Project Mercury and be one of America's first astronauts was a dream come true for test pilot Deke Slayton. But fellow Mercury astronaut Al Shepard kept telling old stories from his native New England, tales of monstrous entities like Cthulhu and Yog Sothoth. Earlier generations had viewed them as demons, but might they in fact be aliens, here long before humanity?

Soon Deke discovers evidence that something is watching the US space program. Something that begrudges humanity the stars and would put a ceiling on human attainment. Something that can manipulate time itself.

HP Lovecraft wrote that we dwell on a placid island of ignorance amidst the dark ocean of infinity, and that we were not meant to travel far.

What might the US space program have looked like in a cosmos filled with hostile eldritch entities? Would they notice us as playthings? Or as a nuisance to be dealt with?