Thirteen-year-old Sophie loves the sea, and she longs to see Bompie, her grandfather who lives in England. So when her three uncles and two cousins decide to sail from their home in the U.S., across the Atlantic Ocean to Ireland, and then to England, to visit Bompie, she begs a place on the boat. She'd be the only girl aboard, though, and Uncle Mo and Uncle Stew don't want to take her. But Uncle Dock knows how important it is to her. So does her father. So they say she can go. Sophie doesn't totally understand why making this trip is important to her. She feels as if the sea is calling her to be away, to be free. But she feels as if something is pulling her back at the same time. She only knows that sailing to Ireland in Uncle Dock's 45-foot sailboat, The Wanderer, to visit Bompie, is something she has to do.

At first the voyage is idyllic. Sophie takes her sleeping bag out on deck and sleeps under the stars. Dolphins play alongside the boat. And Sophie and her cousins lie on deck watching a family of whales --- mother, father, and baby --- swim behind them. But not everything is hugs and kisses. Sophie has to pull her own weight on the boat. Some things are neat, like when she climbs into the bosun's chair and gets hoisted to the top of the mast to fix an anchor light. Neither her cousin Brian nor her cousin Cody will do that, but Sophie loves it. When she has to take her turn killing and cleaning the fish, though, she hates it --- she just won't let anybody know. Everybody has trouble getting along, too. Uncle Stew and his son Brian are bossy, they make lists of what everybody is supposed to do, and they yell at Cody for joking around. Cody's father, Uncle Mo, calls Cody a knuckleheaded doofus.

Uncle Stew decides that everybody has to teach something to the others during the trip, like radio code, how to use a sextant, and how to read charts. Cody teaches them how to juggle. Only Uncle Dock and Sophie really try to learn. Everybody else thinks it's a stupid thing to do. Sophie decides to teach her relatives the stories that Bompie has told her. And she tells great stories about Bompie. The only thing is, Sophie has never met Bompie. And her parents aren't really her parents. They adopted her. Brian needles her all the time about being an orphan, but Sophie acts like she isn't one. And she insists that Bompie told her the stories.

The mystery of Sophie's past bugs Brian. He thinks Sophie lives in a dream world and makes things up. Cody feels sorry for her and wants to know what happened to her real parents. This becomes very important the closer they get to England. Sophie is scared about seeing Bompie, but she doesn't know why. Then a terrible storm engulfs the sailboat, and they all fight for their lives. Sophie's nightmares merge with real life when a gigantic wave rises up out of the ocean and sweeps over the boat. Will they survive?

This book is written in the form of the journals that Sophie and Cody keep during their journey. The mystery builds as the books progresses. Will Sophie live to see Bompie? What will she discover about herself if she does? Is Cody really a knuckleheaded doofus? If you read this book, you won't be able to put it down until you discover the answer to these questions.