While her parents love ""the sameness of their lives,"" Loulou longs for adventure. On her birthday, she gets a package ""from her great-aunt, who was on a fact-finding, fish-gathering expedition on the tiny island of Tumba-Bumba"" and finds inside a fish and a book of instructions (these are written out in longhand and constitute half the text of the book). Loulou follows the instructions, putting away all her old notions about fish and taking Harold (the fish) for a walk in the park, to her dance class, to her tailor (where he is fitted out in tails), and, eventually, to the opera, where he discovers his true calling. He sails away, leaving a crestfallen Loulou with a consolation prize--another fish. Kaleidoscopic gouache illustrations overflow with unlikely details--beginning with a surreal fish parading about town, cats playing fiddles and drums, and dozens of other weird characters. This cerebral book, with its deliberately directionless plot and reliably unpredictable pictures, successfully echoes the signature style of Maira Kalman. What a debut! What a fish!