In a post-apocalyptic Great Britain, after her mother's death Serendipity, about twelve, leaves Lahn Dan and teams up with an orphan, Tab, hoping to find horses surviving somewhere.
While his father fights in the war for water, eleven-year-old Auden and his mother move to Cambridge, where Auden and his new friend Vivi discover his dead uncle's last, unfinished scientific achievement--a poetry-spouting robot seeking his purpose.