The seven survivors of the Welsh expedition to Ireland to rescue Branwen and punish the Irish for dishonoring her went to London to bury Bendigeidfran's head, as per his instructions, facing France to protect against an invasion. With that task completed most headed to their homes. Manawydan, brother of Bendigeidfran who had been king of the territory known as the Isle of the Mighty said, "Alas, I am the only one of us who does not have a home to go to. While the Welsh soldiers had been in Ireland, Caswallawn who had a magic cloak of invisibility had killed all but one of the seven noblemen who had been left to protect the kingdom. The seventh one died of a broken heart. Caswallawn now ruled the Isle of the Mighty.

Another one of the survivors of the Ireland expedition was Pryderi, the son of Pwyll and Rhiannon who had been lost and then found. Pryderi said to Manawydan, "Caswallawn is your cousin. He will let you live in peace in Isle of the Mighty." Manawydan replied, "I would not be able to stand for anyone except my brother Bendigeidfran to be king there." Pryderi then said, "My mother Rhiannon is a widow. I propose that I bestow her upon you as your wife and you live in and enjoy my kingdom of Dyed. In her prime my mother was the finest beauty in the land and she is still pleasant to look at. You will not find a woman who is a more interesting conversationalist than her.

Manawydan said that he would go with Pryderi to see his kingdom of Dyed. They set out toward Dyed. When they arrived at Arberth, the court of Dyed, they found that Rhiannon and Cigfa, the wife of Pryderi, had prepared a great feast for them. Manawydan and Rhiannon spent a good deal time together getting acquainted. Manawydan felt he had never met a finer and more interesting woman than Rhiannon. Manawydan then said to Pryderi, "I accede to what you proposed." Rhiannon then asked, "What proposal was that?" Pryderi then said to her, "My Lady, I have given you to Manawydan as his wife." Rhiannon then replied, "I agree to that gladly." Manawydan then said, "I am also very glad."

The feast continued for several days and Rhiannon was slept with.

The happy couple decided to take break from feasting and went out of the castle and climbed to the top of the mound nearby. This mound was such that any nobles sitting upon it would before left it either suffer a wound or experience a marvel. It was this mound where Pwyll first saw Rhiannon. She was riding on a magical horse.

As they sat on the mound there was a clattering and the falling of mist and fog. The fog became so thick that they could not see one another.

Then the fog lifted. The world around them had changed. None of the people and the farm animals they had seen they went up on the mound were in sight. They walked down from the mound and searched the castle. They could not find anyone or any horses or cows or dogs.

They settled down to live life as the only people in the kingdom and perhaps, in the world. There was plenty of food from the feast. Later they drew upon the stored supplies of the castle. When that was used up they lived by hunting and fishing and an occasional bit of honey. Years passed.

Finally Manawydan said, "We cannot go on living like this. We must go to England and earn our living practicing some craft. So they moved to a town in England and began to make saddles. Manawydan made such beautiful saddles that the other saddle-makers of the town could not compete. The other saddle-makers were outraged that newcomers could come into their town and take the business away. Those other saddle makers decided to kill Manawydan and his companions. Manawydan and Pryderi heard about the saddle makers plans. Pryderi was sure that he and Manawydan as professional military men would be able to kill all of the other saddle makers. Manawydan said they should not fight them because they would get in trouble with the authorities and might be imprisoned. He said they would have to move to a different town.

They did so and in that town decided to make shields. Manawydan and Pryderi made shields so strong and so beautifully painted that they captured the market. The other shield makers of the town seethed with resentment against them and began to talk about murdering them. Pryderi wanted to fight those other shield-makers but Manawydan argued against it and said they must move on to another town.

They did move and when they were settled there Pryderi said, "What shall we do hear?" Manawydan said that they would make shoes. Pryderi said he did not know anything about making shoes. Manawydan said he would teach him to stitch. Manawydan then said they would not make their leather; they would buy the best Cordovan leather they could find. When started producing shoes Manawydan had the shoe buckles gold plated. Consequently their shoes were well made and stylish. Shoe buyers in the town sought shoes from Manawydan and Pryderi in preference to the shoes of the other shoemakers in the town. Again the competitors of Manawydan and Pryderi began to plan to kill them. When Manawydan and Pryderi heard of those plans Pryderi wanted to fight them, but Manawydan said no. Manawydan said that they should return to Dyed and see what was happening there.

So they did return to Dyed taking along their accumulated wealth including a pack of hounds.

Dyed was still deserted but with their hounds they could hunt successfully.

One day Manawydan and Pryderi were out hunting with their hounds. The hounds went into a thicket and then retreated in terror back to the men. The men approached the thicket and the hounds ran back into it and drove out a bright white coated boar. The color of its coated alerted Manawydan that they might be on the edge of the Otherworld.

The boar retreated away from the men but was unaffected by the attempts of the hounds to harass it. So time after time the boar retreated a limited distance and waited until the men came near. The boar was leading the men somewhere.

Soon the men saw a fort standing in a clearing where nothing had stood before. To Manawydan this was clearly something Otherworldly.

The boar went into the fort and the hounds followed. But soon the men heard nothing of the baying of the hounds. Pryderi announced that he was going into the fort to find out what had happened the hounds. Manawydan strongly advised Pryderi against going into the fort, but Pryderi said he could not leave the hounds in such troublesome circumstances.

In the fort Pryderi saw nothing of the hounds or the boar they followed. Instead he saw a fountain with a marble slab and over that slab there was a beautiful large golden bowl hanging from four silver chains that reached up into the sky. He went up to bowl and took hold of it. Instantly his hands stuck to the bowl and his feet stuck to the marble slab where he was standing. He could not say a word.

Outside Manawydan waited and waited but finally had to return to the castle. He told Rhiannon and Cigfa of the misadventure. Rhiannon said, "You were a poor friend to someone who was a good friend to you!"

Rhiannon decided to go herself to find her son Pryderi. She found the fort and went in. She saw Pryderi and the golden bowl. She went up to him and said, "What are you doing here?" She reached to take the bowl from his hand and immediately she was stuck to it and the marble slab under it. When night came there was a clattering sound and a mist descended. When it lifted the fort was gone and Pryderi and Rhiannon with it.

Back at the castle when Manawydan and Cigfa realized Rhiannon was not coming back with Pryderi they both were saddened greatly. Cigfa started crying. Manawydan realized that Cigfa was frightened of living alone with him. I told her he would respect her honor and that she had nothing to worry about concerning him. He said, "I am an old man but even if I were a young man I would respect your honor." Cigfa stopped crying and thanked him for his reassurance. Manawydan said that without their hounds they could not live by hunting here and that they should move to a town in England and make their living by a craft. Cigfa asked what product he would make in England. Manawydan said, "I will make nothing other than shoes, which I have made before.

Again Manawydan's shoes made with fine Cordovan leather and sporting gold-plated buckles were a great success. In due time however he heard of plans by the other shoemakers in town to kill him and Cigfa. He said they must go back to Dyed but this time he would take a load of wheat to plant.

Back in Dyed Manawydan planted three fields of wheat. The wheat in all three fields sprouted and thrived. Near harvest time Manawydan visited one field and saw that it was ready for harvest. He said to himself, "I will harvest this wheat tomorrow." When he came back to that field the next day there was nothing to be harvested. All of the wheat heads were gone and only broken stalks left. He went to the next field and saw that it was ready for harvest. Again he planned to do the harvest the next day, but when he came back the next the field had been stripped of all the wheat heads and only broken stalks were left. So he went on to the third field and saw that it was ready for harvest. He said to himself, "This time I am going to stay in this field and guard it.

He stayed in the third field armed with his weapons. At midnight there was a great clambering and a horde of mice invaded his wheat field. They each ran up a stalk and started biting through the stalk just below the wheat head. Then they got down and carried off the wheat heads. Manawydan tried to stop them but his weapons were useless against them. He managed to capture a pudgy one that was slow. He put it in a glove and tied up the glove opening.

He went back to the castle and told Cigfa what had happened. She asked him what he was going to do with the mouse imprisoned in his glove. He said, "It is a thief who stole from me and I am going to hang it." Cigfa looked at the mouse and identified it as a pregnant female. She said, "Manawydan, a nobleman like you should not concern himself about vermin. You should just let it go." Manawydan said, "No, I am going to hang her as a thief."

Manawydan went out of the castle to the special mound. He started fashioning a gallows for a mouse by sticking two forks into the ground. He then fashioned a hangman's noose in string and put around the mouse's neck. While he was fastening a cross-bar between the two forks for his mouse gallows a student in poor clothing showed up at the mound. This was the first stranger seen in Dyed in seven years. After they exchanged greetings the student asked Manawydan what he was doing. The student said, "I hate to see a nobleman like yourself degrade himself by dealing with vermin. I have a pound's worth of coins I got by begging. I will give them to you if you let the mouse go." Manawydan said, "No, she is a thief and she is going to get a thief's punishment and I will not ransom her." The student left but soon another stranger arrived at the mound. He was a priest. After greetings he asked Manawydan what he was doing and was told. The priest said that rather than see a nobleman dirty his hands on a vermin he would give Manawydan three pounds in money to let the mouse go. Manawydan replied that he would not ransom the mouse and she was going to get the punishment a thief deserved. The priest went on his way.

Just as Manawydan was ready to hang the mouse he saw a bishop arrive with his retinue and baggage. The bishop came up to see Manawydan. They greeted and the bishop gave Manawydan his blessing. But now Manawydan realized that these three successively more prestigious strangers in Dyed where no stranger had been seen in seven years were the wizard from the Otherworld that had put the enchantment on Dyed and abducted Pryderi and Rhiannon.

The bishop first offered the fabulous sum of 24 pounds in money if Manawydan would release the mouse. Manawydan turned the ransom down. The bishop then offered his baggage in return for the mouse. Again Manawydan turned the offer down. The bishop then said in desperation, "Name your price!" Manawydan then said, "I want Pryderi and Rhiannon back." The bishop then said, "Done!" But Manawydan said, "That is not enough. I want the enchantment lifted from Dyed and never imposed again." The bishop said, "You shall have it. Now release the mouse," Manawydan said, "No, there is one more thing: That there not be any revenge imposed upon Pryderi, Rhiannon, Cigfa or me." The wizard in the form of a bishop said Manawydan could have that guarantee." Finally Manawydan asked, "Who is this mouse?" The wizard said, "She is my wife and she is pregnant or you would not have been able to catch her." Manawydan then gave the mouse to the wizard who touched her with his wand and she turned into a beautiful woman.

The wizard identified himself as Llwyd, son of Cil Coed. He said he put the enchantment on Dyed to avenge his friend Gwawl, the unsuccessful suitor of Rhiannon and the victim of the game of Badger-in-the-Bag that Pwyll and Rhiannon had played on him."

The wizard explained that for the first two fields the men of his court were changed in mice to steal the wheat harvest. The women of his court, including his wife, wanted to share this adventure and asked to be turned into mice to steal the harvest of the third field.

Pryderi and Rhiannon then arrived at the mound. The wizard said, "Look around now and you will see that Dyed is as it was before."

Manawydan asked how Pryderi and Rhiannon had been held prisoners. He was told that Pryderi was held down with castle gate-hammers hung around his neck. Rhiannon was held by sweaty horse collars.