"The Rime of the Ancient Mariner", first of all, is a really creepy story. It begins with a wedding, and there are three guests about to enter the wedding celebration, when an ancient, skeleton of a man, (presumably dressed in rags), stops one of them, holding him by the shoulder with a bony hand. He than without a word of warning, or explanation, proceeds to tell a story to the wedding guest, a man he has never met before. .
There was a ship, which set out to sail, and was blown off course, south of the equator, towards the South Pole by a sudden storm. On the voyage home, the ship is encased in a cold fog, and an albatross happens by the ship (not necessarily in that order), and in the fog the ship sails with the albatross, a bird of good fortune. (This is the part where it gets creepy.) Without reason that we know about, the Mariner who narrates the tail shoots the albatross with his crossbow, killing the bird of good fortune, and coincidentally, the fog disperses. The crew of the ship is happy than, thinking that the albatross had brought the fog with it, but after a time, the wind left the ship as well. Without wind for the sails, the boat was dead in the water, and for bringing the ill luck on the crew, the Mariner was sentenced to wear the dead albatross around his neck. .
For weeks the boat sat, unmoving from wind or ocean currents, and the crew was dehydrated. "Water, water, everywhere,/ and not a drop to drink." After a hallucination or two, eventually the crew dies, everyone that is, except for the ancient Mariner. He is left to live on, still wearing the alba-cross (get it?) of penance, and as further punishment, the dead men of the ship still cast their unwavering stares upon him. The only thing that permits him comfort, is the sight of "water snakes" (which I believe are just little waves catching the sun's rays at dusk or dawn). With that bit of comfort in his heart, he is able to pray, and the albatross falls from his neck, and sinks into the sea.