Moby-Dick is widely considered to be the Great American Novel and a treasure of world literature. The story details the adventures of the wandering sailor Ishmael and his voyage on the whale ship Pequod, commanded by Captain Ahab. Ishmael soon learns that Ahab seeks one specific whale: Moby Dick, a ferocious, enigmatic white sperm whale. In a previous encounter, the whale destroyed Ahab's boat and bit off his leg. And Ahab intends to take revenge.