After moving to Cambridge, England, Molly Kimball has found a lot to love, including - of course - her family's ancestral bookshop, Thomas Marlowe-Manuscripts and Folios. And though she's not quite ready to use the "L" word when it comes to her boyfriend Kieran, she's definitely fallen for his intimidating family's library.His family is paying her handsomely for an updated catalog, when Molly discovers the original manuscript of a Gothic novel, A Fatal Folio. Though purportedly written by an ancestor of Kieran's, it was published under the pen name Selwyn Scott, and no one has ever been sure of the author behind the pseudonym. Kieran's cousin, Oliver, offers to pay Molly to help him look into Selwyn's identity. A professor specialising in Gothic literature, he's eager to publish a paper on the mystery - especially because a troublesome student, Thad, is threatening to file a complaint against him and prevent his long-awaited promotion.On Guy Fawkes Night (sometimes known as Bonfire Night), Molly, Kieran, and her friends set out to enjoy the costumes, fireworks, and fun. All goes as planned - at least until a stray firework starts a panic, and the group stumbles upon a prone body, their face covered by a mask. It's Thad: and he's been stabbed to death.It soon becomes clear Oliver isn't the only one with a motive, and Molly must once again put on a few masks of her own to sleuth out Thad's killer, prove Oliver's innocence, and discover what Selwyn's novel might have to do with this most atmospheric mystery...