Here's a summary:
* The mariner stops a wedding guest and tells him his tale. He recounts his journey on a ship that encounters an albatross, a bird considered to bring good luck.
* The mariner shoots the albatross, an act that brings a curse upon the ship. The crew is punished with thirst and a terrible silence, as the albatross hangs around their necks.
* The ship is stuck in the ice and the crew dies of thirst. The mariner is the only one left alive.
* He sees a spectral ship with Death and Life-in-Death playing dice for his soul. Life-in-Death wins, and the mariner is forced to sail alone with the dead crew.
* The mariner begins to pray and find redemption. He learns to appreciate the beauty of the natural world and to see the interconnectedness of all living things.
* The mariner is released from the curse and the albatross falls from his neck. He returns to land and shares his story as a warning about the consequences of harming nature.
The poem explores themes of:
* Nature's power and the consequences of harming it
* The nature of sin and redemption
* The importance of empathy and compassion
* The transformative power of storytelling
The Ancient Mariner's story is a cautionary tale about the importance of respecting nature and learning from our mistakes. It also highlights the power of the human spirit to find redemption even in the face of immense suffering.