A Narrows Escape

From publisher blurb: Mini-Dungeon adventure for 4-5 characters of levels 6-7 The characters are consulting with a scholar at the Great Librarium when an alarm is raised. Someone has broken into the restricted section and stolen The Chained Tome, a book of fiendish lore. Witnesses saw a cloaked figure fleeing the library and heading toward the Narrows, a series of subterranean canals. The characters are asked to follow the thief, in the hopes of catching the criminal before they disappear completely.