The host, a being who does not know what he is or where he came from, survived for centuries by controlling the bodies of small birds and consuming them. When the host has the opportunity to use a human body, he is overwhelmed by the human mind, and for the first time, he can look at himself and try to understand what he is. In his journey for self-knowledge, the host encounters different people, and by controlling their minds, he is able to understand humanity. But the host now knows about the human race, and he does not like what he sees.