The Red Fever, a mysterious virus which erupted in Belgium before spreading all over the world, has brought mankind to the brink of extinction. Children are the only ones left; they remain immune until they reach puberty. Sicily is an abandoned island. Nature is gradually taking back what was once hers, smothering concrete buildings and statues in Baroque palaces with her greenery. The surviving kids have split into anarchic gangs. They scavenge for food amidst the ruined buildings and hulks of abandoned vehicles, or they steal it from one another. Anna Salemi is 14 and lives in a farmhouse hidden in the woods with her little brother Astor. She looks after him, following the instructions in the Book of Important Things their mother left them before she died. Each morning, Anna leaves the house in search of something to eat. But life is tough, and food is scarce. On a day like any other, Anna goes off in search of sustenance, but when she gets home Astor has gone. Someone has kidnapped him. In her quest to find him, she sets off on a hair-raising adventure.