It's for a Book/Playing With

Basic Trope: One character convinces another to give up dangerous and/or plot-relevant information by claiming they're writing a book about it.
 * Straight: Bob convinces a librarian to let him check out books on how to build a pipe bomb by saying he's writing a book about terrorism; he actually needs it to fight vampires.
 * Exaggerated: Bob, a 6th-grade student, convinces the NSA to tell him all about their wiretapping protocols by claiming he's researching surveillance techniques for a class project; he's actually planning on overthrowing the government as soon as he's old enough to be taken seriously.
 * Justified: Bob is a well-known author of Ripped From the Headlines novels, so the librarian should find it very plausible that he'd need to research terrorism for his book.
 * Inverted: Bob is writing a book about terrorism, so he tries to check out books on how to build a pipe bomb in order to see how hard it would be for an actual terrorist to get that information.
 * Subverted: Bob starts to insist to the librarian that, no really, he honestly only wants these books because he's writing a book about terrorism. The librarian cuts him off, says "I don't need to know why you want these books," and gives him the books anyway.
 * Alternately, Bob breaks out the "It's For A Book" excuse to convince the librarian to hand over the books...then in the next scene, it turns out that he really is writing a book on the subject.
 * Double Subverted: As above, but in a later scene from the librarian's perspective it's revealed that she recognized Bob's picture from the back of one of his books, and that's why she didn't need to hear his excuse.
 * Parodied: Bob shows up at a chemistry laboratory with a wheelbarrow full of reagents asking for help manufacturing mass quantities of dynamite "for a book".
 * Deconstructed: The fact that Bob added "It's for a book" to the end of his somewhat-strange request raises the librarian's suspicions. After he leaves she calls the police.
 * Reconstructed: Bob walks into the library carrying a legal pad and a looseleaf binder full of notes, and talks ebulliently about the plot and characters of the supposed novel while checking out a dozen books on a wide variety of subjects -- one of which coincidentally also includes the information he needs.
 * Zig Zagged: In a World where books are illegal, Bob tries to buy a copy of Stephen King's On Writing from a pawnshop. His excuse to the pawnshop owner that he's not planning on using it as an instruction manual for writing novels; it's just that one of the characters in his latest novel is an author and he's trying to get inside his character's head.
 * Averted: Bob checks out books about pipe-bomb building from the library. He doesn't explain why he needs them, and the librarian doesn't ask.
 * Enforced: ???
 * Lampshaded: "That sounds like a really exciting novel you're writing!"
 * Invoked: Bob actually is a novelist who has happened to get caught up in a real adventure involving vampires. He reasons that he might as well approach the adventure as if it were one of his novels and do research on the subject in the same way -- and maybe even get a few ideas for his latest novel in the process.
 * Defied: Before Bob can start making excuses, the librarian says, "Don't bother tell me you're writing a book; I know that's what all the vampire hunters say."
 * "You're a novelist. Make something up."
 * Discussed: ???
 * Conversed: ???

Back to the main page. (Beat) ...It's for a book, I swear!