Puzzling plots.

Grossman, Lev. CODEX. This thrilling novel twists and turns as Edward, an investment banker commissioned to organize a library, finds himself searching for a mythical codex that may or may not exist.

Martin, William HARVARD YARD. Rare book dealer Peter Fallon gets caught up in a quest to find "a gift of majestic proportions," a book donated to Harvard College by John Harvard. The story moves from the present to the past as it intertwines the fascinating history of Harvard with the richly detailed Wedge family.

Caldwell, Ian. RULE OF FOUR. In a story reminiscent of The Da Vinci Code, four Princeton classmates become entangled in the quest to find the Hypnerotomachia Poliphili, an actual text that perhaps holds hidden codes to Roman buried treasure.

Westerfeld, Scott. SO YESTERDAY. Spending his afternoons and weekends prowling the New York streets looking for "cool," innovative fashion trends, Hunter and his girlfriend stumble upon a conspiracy causing him to redefine his very notion of "cool."

Wynne, Tim Jones. A THIEF IN THE HOUSE OF MEMORY. The death of an apparent stranger in the Steeple family's old home triggers troubling questions for sixteen-year-old Declan. Hoping to learn the truth about the mother who suddenly left when he was ten, he tries to make sense of his fragmented dreams, random memories, and unexplained coincidences.

Picoult, Jodi. VANISHING ACTS. Life turns upside down for Delia Hopkins when everything she thought was true is revealed to be a lie and she is forced to conduct a search-and-rescue mission on her own past and identity.