When the author heard of the mysterious loss of thousands of bath toys at sea, he figured he would interview a few oceanographers, talk to a few beachcombers, and read up on Arctic science and geography. But questions can be like ocean currents: wade in too far, and they carry you away. His accidental odyssey pulls him into the secretive world of shipping conglomerates, the daring work of Arctic researchers, the lunatic risks of maverick sailors,...