Despite the fact that this is a post-apocalyptic story in which the few remaining humans are kept in captivity, this is a feel-good Science Fiction novel.
The lightness in tone comes mainly from the innocence and empathy of the main character, Heyou, a Servile Unit (an A.I. in a humanish body) whose purpose is the care and feeding of humans in their compound.
Heyou, the Wrong Unit of the title, is picked up by mistake and thrust into an epic quest to save humanity.
This involves a very long walk with a very small child. As Heyou trudges across the planet his empathy for humans and his own sense of identity grows with each challenge that he overcomes. Eventually, he has to face the biggest challenge of all, freeing humanity by bringing down Core, the A.I. who made him.
Rob Dircks is both author and narrator of this novel and he does both jobs with a deft touch and a nuanced understanding of dialogue and interior monologues.
This book is packed with clever ideas and finds new twists on the A.I. – menace-to-humanity trope but its strength comes from the gradual growth of Heyou into a fully rounded person.
Pick this one up if you want a light, fast, upbeat read.