Fred Hoyle's scientific pedigree is up front in this vintage novel, co-written with son Geoffrey. The story is based on a classic SF premise--a star, with its own planetary system, is heading towards our own. It passes close enough for us to mount an expedition to one of the planets of the visiting star--an earth-like world with detectable signs of plant life. The planet turns out to be inhabited by vastly superior telepathic beings who hide themselves from the visitors. One of them takes possession of the mind of an astronaut, returning to earth to spread a dramatic and unwanted telepathic warning against the nuclear arms race, before returning on a hijacked spacecraft.