From the Los Angeles Opera website:
Moby-Dick is an opera in two acts based on the classic novel by Herman Melville. Set in 1820, it tells the story of Ahab, captain of the whaleship Pequod, and the crew he commands. After losing one of his legs to a fearsome white whale, Captain Ahab becomes obsessed with finding and destroying the creature at any cost. Only one crew member, first mate Starbuck, realizes the deadly implications of Ahab’s obsession.