Dive in to this whimsically adventurous graphic novel from Caldecott Medalist Dan Santat! Ever since her father was lost at sea, Sophia has been moping around Aqualand, the marine theme park her dad and uncle created. But Sophia's world is turned upside down when an "aquanaut" breaks into the park's research lab. To her amazement, Sophia discovers that the aquanaut is not what it seems -- inside lives a band of four goofy sea creatures! And...

An imaginary friend waits a long time to be imagined by a child and given a special name, and finally does the unimaginable--he sets out on a quest to find his perfect match in the real world.