Act I
Scenes 1 to 4. Day One: The whaling ship Pequod has been at sea for one week
Captain Ahab stands alone on deck in the hours before dawn. Below deck, while most of the crew sleeps, the harpooner Queequeg prays and wakes Greenhorn, a loner and newcomer to whaling. Dawn breaks and the call is made for "All Hands!" While the crew is raising the ship's sails, Starbuck, Stubb, and Flask talk about Ahab, whom no one has seen since the ship left Nantucket.
The crew sings of whales, wealth, and home until suddenly, Captain Ahab appears. He tells them of Moby-Dick, the white whale that took off one of his legs, then nails a gold doubloon to the mast and promises it to the man who first sights him. This is the real reason they have sailed, he explains: to search the globe to find and destroy this one whale. His rousing call of "Death to Moby-Dick!" excites everyone but the first mate, Starbuck. To no avail, he confronts Ahab about what he sees as a futile and blasphemous mission.
Starbuck instructs Greenhorn about the dangers of whaling. When he ponders never again seeing his wife and son, he is overcome with emotion and orders Queequeg to complete the lesson. Stubb sights a pod of whales, but Ahab will not allow the eager crew to hunt since they have not yet found Moby-Dick. Starbuck orders the crew to sail on and sends Greenhorn up to the lookout on the masthead, joined by Queequeg.
As the sun begins to set, Ahab looks over the wake of the ship and mourns that his obsession deprives him of any enjoyment of beauty. All is anguish to him. At the masthead, Queequeg and Greenhorn look over the world, while Starbuck, on deck, bemoans Ahab's madness.
Scenes 5 to 7. Day Two: Three months later
After three months without a single whale hunt, Stubb jokes with the young cabin boy Pip about the sharks circling the ship. The song ignites a dance for the full crew, but rising tensions take over and a dangerous racial fight erupts. When Greenhorn suddenly sights a pod of whales, Starbuck is at last able to persuade Ahab to let the men hunt. Starbuck and Stubb harpoon whales, but Flask's boat is capsized and Pip is lost at sea.
On board the Pequod, an enormous whale is being butchered and the oil rendered in the burning tryworks. Flask tells Ahab that the search for Pip is under way, but Ahab thinks only of finding Moby-Dick. As they butcher the whale, the crew imagines Pip lost and struggling in the heart of the sea. Flask tells Starbuck that many oil barrels are leaking. Concerned, Starbuck goes below to tell Ahab they must find a port for repairs.
Ahab is unmoved by Starbuck's report, and is concerned only with the white whale. When Starbuck refuses to leave, Ahab grabs a musket and orders him to his knees. From afar, Greenhorn shouts that Pip has been found. Ahab orders Starbuck out of the cabin.
On deck, the crew listens to Greenhorn describe how Queequeg rescued Pip. As the men return to work, Greenhorn pleads with Starbuck to get help for Pip, who has gone mad. But, the first mate ignores him. Greenhorn observes how life really works on the ship and decides to befriend Queequeg.
Starbuck returns to Ahab's cabin, where he finds the captain asleep. He picks up the musket with which Ahab had threatened him and contemplates what he should do. Pull the trigger and he may survive to see his wife and child again. When Ahab cries out in his sleep, Starbuck replaces the musket and leaves the cabin.
Act 2
Scenes 1 to 3. Day Three: One year later
An enormous storm is approaching, but Stubb, Flask, and the crew sing a jolly work song. From the mastheads, Greenhorn and Queequeg talk of traveling together to his native island. Greenhorn wants to learn Queequeg's language and write down their adventures. Suddenly, Queequeg collapses. The crew gets him down and Ahab announces he will take the masthead watch himself, as he wants to sight Moby-Dick first.
Below deck, Queequeg tells Greenhorn that he is dying and asks that a coffin be built for him. Pip enters from the shadows and sings a lament, joined by Greenhorn.
The massive storm now surrounds the Pequod. As Ahab sings defiantly to the heavens, bolts of lightning engulf the ship and the masts glow with St. Elmo's fire. Ahab demands that the men hold their posts, promising them the white flame is a sign from heaven to guide them to the white whale. The crew is inspired once again by the captain, much to Starbuck's distress.
Scenes 4 to 7. Day Four: The next morning
The ship has made it through the storm. From afar, the voice of Gardiner, captain of the Rachel, calls out. He pleads with Ahab to help him search for his 12-year-old son who was lost in the storm, but Ahab refuses. Pip shouts to Gardiner of the Pequod's own lost boy. Pip cuts himself and gets blood on Ahab's clothes. The captain orders the ship to sail on, leaving Gardiner behind. Ahab contemplates the heartless God who devastates so many lives and baptizes his new harpoon with Pip's blood.
Below deck, Greenhorn sees Queequeg's newly-built coffin and contemplates the madness that seems to surround him.
On deck, Ahab and Starbuck gaze over the horizon. Ahab describes his forty years at sea and all he has left behind. And why? To what end? He cannot say. But he sees in Starbuck's eye a human soul and it touches him deeply. Starbuck seizes the moment and persuades Ahab that they should return to the wives and sons who wait for them in Nantucket.
Just as Ahab appears to relent, he sights Moby-Dick on the horizon. Great excitement ensues and the whale boats are lowered. Ahab looks again in Starbuck's eye and orders him to stay on board. The crew declares its loyalty to Ahab. During the chase, Moby-Dick destroys two whaleboats in succession, drowning their crews. Then, the Pequod is rammed and sunk, killing all aboard. Ahab's boat is then attacked and all but the captain jump or fall off. Finally alone with the white whale, Ahab cries out and stabs at Moby-Dick before being dragged down into the sea.
Epilogue: Many days later
Greenhorn floats on Queequeg's coffin, barely alive, softly singing his lost friend's prayer. Gardiner calls from afar, thinking he has at last found his missing son. Instead, he learns that Ahab and all the crew of the Pequod have drowned, except for this one survivor.
