You have thirteen book covers, torn in half. Each half-cover includes a character name at the top and part of a title; the right half-covers also include some number of clipart glyphs related to the title, while the left half-covers have some number of handcuffs. The placement of the character names suggests that, when reassembled, each cover will say something like “So-and-so & Thus-and-such IN”: so these look like recurring characters, already familiar to the reader from earlier books in the series.

Each of the rather unusual character names given shares a (more or less cockeyed) member-of-common-set relationship with the name of a famous detective or that detective’s partner from detective fiction. The nature of these relationships is hinted in the flavortext: “Gedult’s & Alkaline Earth, Booksellers” maps to the familiar Barnes & Noble, Booksellers (Gedult’s and Barnes are both chess openings; “alkaline earth” and “noble” are both the adjectival parts of informal names of periodic table groups). Working out these relationships allows you to reassemble the pairs:

Having assembled the book covers, you now know the full titles. Each pair of real characters recurs in a finite set of stories; as suggested by the flavortext (“mixed-up titles,” “blatantly derivative works”), the fake title is an anagram of one of the real titles in this set. (Leading articles, “Adventure of the,” and “Case of the,” all typeset in smaller font, are excluded from the anagrams.) The price stickers, for unique values from $1.99 to $13.99, should suggest themselves as the ordering mechanism. (You might be tempted to alphabetize by author. To maybe dissuade you a bit, the fake authors’ names are all synonyms for RED HERRING.) The title-specific clipart glyphs on the right half of each cover provide an index into the original title. (This indexing step excludes any portion of the title that wasn’t anagramed: leading “The,” “The Adventure of the,” “The Case of the”; these excluded portions are typeset to match the red-herring authors.) The indicated letters spell out FIND THE CROOKS.

Search for spoilers (all findable in plot summaries, Goodreads reviews, etc.); the post-it note, with spoilers alphabetized by first name and then redacted, should clear up any ambiguities (e.g., are you looking for Sir James Peel Edgerton, or just James Peel Edgerton?). Where the book has been adapted for TV or film and character names have been changed, you of course want the book version. Now collar the crooks: the number of sets of handcuffs on the left half of each cover gives you an index into the villain’s name. In price order, these extracted letters spell TEAR US A NEW ONE. (We hope that you will interpret this to mean “mock up a new cover in this vein and tear it in half,” but there’s some flexibility.)

Solvers who came to HQ to TEAR US A NEW ONE watched as we tore up a folded piece of paper in front of them, and were then handed the pieces. On reassembling the pieces, solvers found yet another mystery cover (this one from a real book), with a piece missing. What remains is the author’s name, Carter Dickson; the art; and the beginning of the title, Seeing is. The answer to the puzzle is the rest of the title: BELIEVING.