The time is the late 21st century, and the aliens have arrived. Sixty-five thousand unknown objects, in perfectly symmetrical formation, simultaneously burn up in the Earth's atmosphere. An unmanned probe, far out at the edge of the Solar System, detects the faint trace of communications from a large asteroid, aimed further out into space. High-velocity remote probes are sent from Earth, but the asteroid explodes. A manned ship, crewed by a handful of radically adapted specialists, follows the communication trace out towards the Oort Cloud. Their leader is a vampire.
Some time before, it had been discovered that vampires once existed before being killed off by humans at the dawn of civilisation. Their genome had been retrieved from ancient remains and they had been reconstructed. They are top predators (humanity being their favoured prey) who can paralyse people with fear just by looking into their eyes, and were only defeated because they suffer a massive seizure and become helpless at the sight of right-angles – such as a cross. To overcome this they are given a medicine which also tames their predatory instincts; they are valued because they are vastly more intelligent than humans. Their ability to hibernate in a near-death state for months or years has been transferred to the humans who form the rest of the crew, allowing them to make the long, slow journey.
One of the crew is Siri Keeton, a synthesist with half his brain removed in childhood to cure his constant and violent seizures. The vacated space is now filled with technology used to enhance his autistic ability to dispassionately observe and analyse events - and especially the rest of the crew - in order to keep an objective record to send back to Earth.
They manage to track down the destination of the signal, a bizarre alien craft orbiting a brown dwarf star, too dim to have been detected from Earth. The craft appears to be growing but its nature, and that of what the crew assume to be the aliens inhabiting it, makes no sense. The crew struggle to understand what is happening, and suffer increasing stress as the situation deteriorates beyond their control.
Blindsight is an ambitious epic of first contact, in the best tradition of hard SF. It is packed full of original and sometimes startling ideas, and richly deserved the Hugo nomination it received when published a few years ago. However, I have to say that I did not find it an easy read. The very density of ideas slows the pace, while the reader is made to work hard to follow what is going on. I found that I could only read it in small doses so it took me over a week to complete. It was worth the effort, though the conclusion is not one that optimists will enjoy.