Peppa Danyelle didn't buy a bookstore to solve murders. She bought it for the quiet.

After a decade of corporate actuarial work that aged her a solid eight years, Peppa cashed in everything she had for Shelf Life, a used bookstore in Salem's historic district. Low foot traffic. Thriving online sales. Ten customers a day, max. The math worked. The dream worked. For exactly one week.

Then a retired antiques dealer was found dead in his locked study two blocks away. Police ruled it suicide. And a man appeared in Peppa's mystery section — tall, angular, Victorian, and deeply unimpressed with her shelving system.

He introduced himself as Sherlock Holmes. He said the dead man was murdered. He was right about the shelving, too, which was the more annoying part.

Now Peppa can see a fictional detective no one else can see, she's receiving deductions she can't explain to the actual police, and her carefully constructed quiet life is becoming the loudest thing in Salem. The locked room has a secret. The suicide note is a forgery. And somewhere between the bookshelves and the crime scene, there's a passage that someone went to a great deal of trouble to hide.

Peppa was an actuary. She knows what patterns look like. She also knows the probability of Sherlock Holmes being real is exactly zero. And yet.