Summer is Hayley’s favorite time of the year, mostly because there’s no homework, or staying after school for detention. But she also has more time to hang out with her friends, especially her fraternal twin, Arthur. She wears a lot of socks, sometimes seven pairs if she can get her foot inside of her sneakers. Her lucky number is seven, and the socks help keep her Something Awfuls away — the gut feeling that something terrible will happen. When she’s not plotting revenge on her nemesis, Hayley makes remedies from herbs.
Arthur wears a brace around his leg, which was mangled pretty badly in an accident. He likes to experiment with herbs in the basement with Hayley, his twin and buddy, and formulate new herbal remedies that his mom sells in her café in the bookstore that she owns. His other favorite thing is magic tricks and showing off his skill in front of his friends — the harder the trick, the better. Secretly, he hopes to find his father, who supposedly died in a plane crash before he and Hayley were born. Arthur believes he is still alive in a jungle in Peru.