Book excerpt: Beware the mysteries of the deep sea, including Trenchbillies, the Bikini Bottom Triangle, Hagfish Hex, and the Main Drain! Far below the surface of the ocean’s crystal blue waters are strange tales that have remained mysteries—until now when SpongeBob is the only one brave enough to unravel the hidden secrets of the deep! Based on Nickelodeon's hit series, SpongeBob SquarePants.