The Case of the Curiously Correct Blueprints

From BoardGameGeek:

As a member of the SHhhh, We're Reading Book Club in Hincksville, you've been patiently awaiting your turn to read the advance copy of the highly anticipated new Ells and Ernie mystery, when Mr. Hincks gives you some shocking news: your copy of the book is at the bottom of a vat of candy! Never fear, Mr. Hincks will save the day! (Which is only fair, seeing as he was the one that ruined the day.) Mr. Hincks has recorded an abridged audio version of the book and put together a box of peculiar reference materials in order to recreate the story for you before the book club meeting. But there's one problem: the first rule of book club is, NO SPOILERS! How can Mr. Hincks recap this mystery book for you without spoiling any of the twists? You're not quite sure, but he seems to have a few puzzling tricks up his sleeves. Can you unlock all the audio clips before the SHhhh, We're Reading Book Club meeting? What are these mysterious markups on the reference pages?? How can a set a blueprints that are correct be curious??? Answer all of these questions and more in... The Case of The Curiously Correct Blueprints! -description from the publisher