The story begins with a man named Eriol, as he lands on the 'Lonely Island' mythical prehistory England. While traveling he stops at the "Cottage of Lost Play" a house owned by Lindo and Vairë elves. They tell him how they came to be there, and of a place called the 'Cottage of Children', a place where Children that had gotten lost in the woods could stay. Its caretaker left and the cottage was rediscovered by Lindo's father, and he took the children to this island, with him, and now Lindo looks after them.

The next day Eriol walks in the garden and meets the door man, and is told the story of "The Music of the Ainur". A creation myth where the creator sings into being immortal spirits, that with their help sing into being the world. One of these spirits becomes evil, and begins to dislike the two races that are placed within the world, Elves and Men. Some of the spirits decided to be caretakers for the world and broke up into two groups the Valor, care takers and the Maia, servants to them.

That night he asks to hear more stories, and is told "The Coming of Valor and the Building of Valinor". the care takers have their own parts of the world, but eventually get together and create a can all live in the world. They placed it on the war West of the world and they call it Valinor, all but the evil one decided to live there, he made his home in the mountains of the north.

Eriol soon wishes to stay on the island, but must get the queen's permission, but she tells him he must learn more about them first. She then tells him of "The Chaining of Melko". It tells how the evil one tried to destroy that which the other Valor created and how subdued him and put him on trial for his crimes.

Eriol then asks about the elves and is told "The Coming of the Elves and the Making of Kôr." Near the end of the evil ones imprisonment the Elves came into being, and seeing them, the Valor requested to talk with them, but only three came to Valinor, of these three the original three tribes of Elves grew, of these many returned and built the city Kôr near Valinor. Here the magic Silmarillion jewels.

The queen ends her story, and Eriol returns to Lindo's house, where at story time Lindo tells "The Theft of Melko and the Darkening of Valinor" This tells how the evil one causes distrust between the elves and the Valor, then while the elves are at Valinor the three Silmarils. He hides in a cave and meets a spider woman that offers to help him, and together they go to Valinor, and destroy the two Trees of Light, they are almost caught but manage to escape, with the help of the spider woman's power to cause darkness.

The story continues without a break, but with a new title "The Flight of the Noldoli". One of the groups of elves gets restless after helping hunt for the evil one, they feel ill used and steal boats from another group, they become exiles and escape to the East and to the continent.

Some time later a guest arrives and Lindo tells "The Tale of the Sun and Moon". It tells that after Valinor was darkened, they cried over the trees which made bloom one last fruit, it shined brightly and they placed it in the sky. One of the valor sing to the other tree and then touch it as it brings a blossom of a fruit but it is dropped and the fruit doesn't shine as brightly, they place it in the sky also, where they will now be the moon and sun.

Lindo asks his wife to tell the next story which is, "The Hiding of Valinor" This tells how the valor feared evil would return so they destroy all roads leading to Valinor, and the only way for the elves to reach there is by a bridge rainbow, that is really the hair of a Valor. Then three strangers come to Valinor and they asked to take hold of the sun, and moon, and with a cord they bind them together, and create the days, months and years. They then introduce themselves as the sons of time.

Time passes and the new guest to the cottage is asked to tell a story, he then tells, "Gilfanon's Tale: The Travail of the Noldoli and the Coming of Mankind". The story starts with elves that did not go to Valinor but stayed where they awakened, they were taught forbidden things by a wizard. They found men sleeping in caves and woke them up. At first they were friends by the evil one sent messengers to make men and elves hate, a war broke out, and men where beaten and driven away. They get together with the Noldoli who left Valinor, and try to fight the evil one but lose and some are turned into slaves while the two groups of elves learn to distrust each other.

The new guest's story ends and he leaves, while Eriol remains at Lindo's for a while longer. The story continues in "The Book of Lost Tales: Part II".