Then Felagund gave the crown of Nargothrond to Orodreth his brother to govern in his stead; and Celegorm and Curufin said nothing, but they smiled and went from the halls.
On an evening of autumn Felagund and Beren set out from Nargothrond with their ten companions; and they journeyed beside Narog to his source in the Falls of Ivrin. Beneath the Shadowy Mountains they came upon a company of Orcs, and slew them all in their camp by night; and they took their gear and their weapons. By the arts of Felagund their own forms and faces were changed into the likeness of Orcs; and thus disguised they came far upon their northward road, and ventured into the western pass, between Ered Wethrin and the highlands of Taur-nu-Fuin. But Sauron in his tower was ware of them, and doubt took him; for they went in haste, and stayed not to report their deeds, as was commanded to all the servants of Morgoth that passed that way. Therefore he sent to waylay them, and bring them before him.
Thus befell the contest of Sauron and Felagund which is renowned. For Felagund strove with Sauron in songs of power, ad the power of the King was very great; but Sauron had the mastery, as is told in the Lay of Leithian:
Then Sauron stripped from the their disguise, and they stood before him naked and afraid. But though their kinds were revealed, Sauron could not discover their names or their purposes.
He cast them therefore into a deep pit, dark and silent, and threatened to slay them cruel, unless one would betray the truth to him. From time to time they saw two eyes kindled in the dark, and a werewolf devoured one of the companions; but none betrayed their lord.
In the time when Sauron cast Beren into the pit a weight of horror came upon Lúthien's heart; and going to Melian for counsel she learned that Beren lay in the dungeons of Tol-in-Gaurhoth without hope of rescue. Then Lúthien, perceiving that no help would come from any other on earth, resolved to fly from Doriath and come herself to him; but she sought the aid of Daeron, and he betrayed her purpose because he would not deprive Lúthien of the lights of heaven, lest she fail and fade, and yet would restrain her, he caused a house to be built from which she should not escape. Not far from the gates of Menegroth stood the greatest of all the trees in the Forest of Neldoreth; and that was a beech-forest and the northern half of the kingdom. This mighty beech was named Hírilorn, and it had three trunks, equal in girth, smooth in rind, and exceeding tall; no branches grew from them for a great height above the ground. Far aloft between the shafts of Hírilorn a wooden house was built, and there Lúthien was made to dwell; and ladders were taken away and guarded, save only when the servants of Thingol wrought her such things as she needed.
It is told in the Lay of Leithian how she escaped from the house in Hírilorn; for she put forth her arts of enchantment, and caused her hair to grow to great length, and of it she wove a dark robe that wrapped her beauty like a shadow, and it was laden with a spell of sleep. Of the strands that remained she twined a rope, and she let it down from her window; and as the end swayed above the guards that sat beneath the house they fell into a deep slumber. Then Lúthien climbed from her prison, and shrouded in her shadowy cloak she escaped from all eyes, and vanished out of Doriath.
It chanced that Celegorm and Curufin went on a hunt through the Guarded Plain; and this they did because Sauron, being filled with suspicion, sent forth many wolves into the Elf-lands. Therefore they took their hounds and rode forth; and they thought that ere they returned they might also hear tidings concerning King Felagund. Now the chief of the wolf hounds that followed Celegorm was named Huan. He was not born in Middle-earth, but came from the Blessed Realm; for Oromë had given him to Celegorm long ago in Valinor, and there he had followed the horn of his master, before evil came. Huan followed Celegorm into exile, and was faithful; and thus he too came under the doom of woe set upon the Noldor, and it was decreed that he should meet death, but not until he encountered the mightiest wolf that would ever walk the world.
Huan it was that found Lúthien flying like a shadow surprised by the daylight under the trees, when Celegorm and Curufin rested a while near to the western eaves of Doriath; for nothing could escape the sight and scent of Huan, nor could any enchantment stay him, and he slept not, neither by night nor day. He brought her to Celegorm, and Lúthien, learning that he was a prince of the Noldor and a foe of Morgoth, was glad; and she declared herself, casting aside her cloak. So great was her sudden beauty revealed beneath the sun that Celegorm became enamoured of her; but he spoke her fair, and promised that she would find help in her need, if she returned with him now to Nargothrond. By no sign did he reveal that he knew already of Beren and the quest, of which she told, nor that it was a matter which touched him near.
Thus they broke off the hunt and returned to Nargothrond, and Lúthien was betrayed; for they held her fast, and took away her cloak, and she was not permitted to pass the gates or to speak with any save the brothers, Celegorm and Curufin. For now, believing that Beren and Felagund were prisoners beyond hope of aid, they purposed to let the King perish, and to keep Lúthien, and force Thingol to give her the mightiest of princes of the Noldor. And they did not purpose to seek the Silmarils by craft or war, or to suffer any others to do so, until they had all the might of the Elf-kingdoms under their hands. Orodreth had no power to withstand them, for they swayed the hearts of the people of Nargothrond; and Celegorm sent messengers to Thingol urging his suit.