The poem begins with an old grey-bearded sailor, the Mariner, stopping a guest at a wedding ceremony to tell him a story of a sailing voyage he took long ago. The Wedding-Guest is at first reluctant to listen, as the ceremony is about to begin, but the mariner's glittering eye captivates him.
The mariner's tale begins with his ship departing on its journey. Despite initial good fortune, the ship is driven south by a storm and eventually reaches the icy waters of the Antarctic. An albatross appears and leads the ship out of the ice jam where it is stuck, but even as the albatross is fed and praised by the ship's crew, the mariner shoots the bird:
The crew is angry with the mariner, believing the albatross brought the south wind that led them out of the Antarctic. However, the sailors change their minds when the weather becomes warmer and the mist disappears:
They soon find that they made a grave mistake in supporting this crime, as it arouses the wrath of spirits who then pursue the ship "from the land of mist and snow"; the south wind that had initially blown them north now sends the ship into uncharted waters near the equator, where it is becalmed:
The sailors change their minds again and blame the mariner for the torment of their thirst. In anger, the crew forces the mariner to wear the dead albatross about his neck, perhaps to illustrate the burden he must suffer from killing it, or perhaps as a sign of regret:
After a "weary time", the ship encounters a ghostly hulk. On board are Death (a skeleton) and the "Night-mare Life-in-Death", a deathly pale woman, who are playing dice for the souls of the crew. With a roll of the dice, Death wins the lives of the crew members and Life-in-Death the life of the mariner, a prize she considers more valuable. Her name is a clue to the mariner's fate: he will endure a fate worse than death as punishment for his killing of the albatross. One by one, all of the crew members die, but the mariner lives on, seeing for seven days and nights the curse in the eyes of the crew's corpses, whose last expressions remain upon their faces:
Eventually, this stage of the mariner's curse is lifted after he begins to appreciate the many sea creatures swimming in the water. Despite his cursing them as "slimy things" earlier in the poem, he suddenly sees their true beauty and blesses them ("A spring of love gush'd from my heart, And I bless'd them unaware"). As he manages to pray, the albatross falls from his neck and his guilt is partially expiated. It then starts to rain, and the bodies of the crew, possessed by good spirits, rise again and help steer the ship. In a trance, the mariner hears two spirits discussing his voyage and penance, and learns that the ship is being powered supernaturally:
Finally the mariner wakes from his trance and comes in sight of his homeland, but is initially uncertain as to whether or not he is hallucinating:
The rotten remains of the ship sink in a whirlpool, leaving only the mariner behind. A hermit on the mainland who has spotted the approaching ship comes to meet it in a boat, rowed by a pilot and his boy. When they pull the mariner from the water, they think he is dead, but when he opens his mouth, the pilot shrieks with fright. The hermit prays, and the mariner picks up the oars to row. The pilot's boy laughs, thinking the mariner is the devil, and cries, "The Devil knows how to row". Back on land, the mariner is compelled by "a woful agony" to tell the hermit his story.
As penance for shooting the albatross, the mariner, driven by the agony of his guilt, is now forced to wander the earth, telling his story over and over, and teaching a lesson to those he meets:
After finishing his story, the mariner leaves, and the wedding-guest returns home, waking the next morning "a sadder and a wiser man".
