Secret by Pseudonym Bosch Books in Order

Eleven-year-olds Cass and Max-Ernest find a box of strange scent vials and follow the trail of a vanished magician. Their search leads to dangerous villains, baffling clues, and a secret that was meant to stay hidden.

Cass and Max-Ernest receive their first assignment from the mysterious Terces Society and discover the Museum of Magic. A missing Sound Prism, a bottled creature, and old enemies pull them closer to a secret someone will kill to possess.

Cass's mother is kidnapped by Señor Hugo, a dessert chef with a dangerous obsession. To get her back, Cass and Max-Ernest must find a legendary tuning fork and uncover the troubling secret behind his extraordinary chocolate.

Cass wakes alone in a strange medieval world while, back home, she lies in a deep coma after eating Time Travel Chocolate. Max-Ernest must find a cure as Cass searches for family clues and a route back.

Cass breaks a finger from a priceless mummy during a museum field trip, and soon she, Max-Ernest, and Yo-Yoji are blamed when worse trouble follows. Clearing their names means chasing clues through tombs, hieroglyphs, and the final Secret.

The author has left a mystery unfinished and insists that the reader must complete it. Prompts, puzzles, and story games guide budding writers through creating their own adventure while following a playful case.