A thrill of discovery coursed through Shellington as he unearthed the unique tooth of a spade-toothed beaked whale, a creature rarely seen. Now, the Octonauts face a new mission: to locate the whale that lost the tooth, so Shellington can study this remarkable specimen and Peso can offer assistance in finding a replacement. The task, however, will prove challenging. Spade-toothed beaked whales are solitary creatures, preferring undisturbed waters, and they possess an extraordinary ability to dive to incredible depths.