Matilda Whipplethorn is about to get what she's always wanted, and it's a bad thing. Being a babysitter isn't much of a dream for the average thirteen-year-old, but Matilda is anything but average. She's half a centimeter tall, invisible to the human eye, and hearing-impaired. Her mother won't let her forget any of that. So for Matilda, adventures are in short supply. Finally agreeing to let Matilda take some responsibility, her mother gives her a list of emergency procedures for babysitting.
It's summer in St. Louis and Mercy Watts is on vacation from her parents. The great detective and his nosy wife are on a cruise and Mercy thinks she's off the hook for doing any investigating for them. But when a family friend has a fatal heart attack, Dad has one of his famous feelings and orders Mercy to look into it. Mercy tries not to get sucked in. She really does, but she's her father's daughter. Soon Gavin's death leads to a more grisly one, the death of a bride on her wedding day. Can the two be connected?
Vacations can be murder, especially when you're Mercy Watts. She's trying to get away from it all, including her godmother's lawsuit and a certain situation with the mafia. So she heads to Roatan, Honduras, a place known for scuba diving and lawlessness. Mercy's on the island less than 24 hours when she discovers that she hasn't gotten away from anything. Her problems hitched a ride and increased tenfold. The deeper she dives, the more dangerous her vacation becomes.
After surviving a kidnapping and battling with spriggans, Matilda Whipplethorn finds her life in a suburban human house pretty boring. She's been excluded from school because of her fire-making abilities and her former friends are afraid of her. Salvation comes in the form of a life-threatening illness. Her tutor, Miss Penrose, needs a medication and there's only one place to get it, the spriggans. Matilda heads back to the antique mall to save Miss Penrose even though it just might cost her everything.
"An Engaging Narration"
Matilda Whipplethorn thought her mission would be simple. She'd get the cure for Miss Penrose and get out, but nothing is simple in Paris. The fairy revolution is heating up, not cooling down as the Whipplethorns were told. Navigating the city comes with unexpected dangers, blood-thirsty rebels, tyrannical royalists, and monsters of all kinds. The Vermillion clan holds the cure, and they're in hiding. Every time Matilda asks a Parisian fairy about the Vermillion, she becomes their enemy in a city that is now all enemies and no allies.