The opening scene is in a forest, in an unknown land.  It is autumn.  Golaud, gray-bearded, stern, a giant in stature ("I am made of iron and blood,” he says of himself), has been hunting a wild boar, and has been led astray.  His dogs have left him to follow a false scent.  He is about to retrace his steps, when he comes upon a young girl weeping by a spring.  She is very beautiful, and very timid.  She would flee, but Golaud reassures her.  Her dress is that of a princess, though her garments have been torn by the briars.  Golaud questions her.  Her name, she says, is Melisande; she was born “far away;” she has fled, and is lost; but she will not tell her age, or whence she came, or what injury has been done her, or who it is that has harmed or threatened her—­“Every one! every one!” she says.  Her golden crown has fallen into the water—­“It is the crown he gave me,” she cries; “it fell as I was weeping.”  Golaud would recover it for her, but she will have no more of it....  “I had rather die at once!” she protests.  Golaud prevails upon her to go with him—­the night is coming on, and she cannot remain alone in the forest.  She refuses, at first, in terror, then reluctantly consents.  “Where are you going?” she asks.  “I do not know....  I, too, am lost,” replies Golaud.  They leave together.

The scene changes to a hall in the castle—­the silent and forbidding castle near the sea, surrounded by deep forests, where Golaud, with his mother Genevieve and his little son Yniold (the child of his first wife, now dead), lives with his aged father, Arkel, king of Allemonde.  Here, too, lives Golaud’s young half-brother, Pelleas—­for they are not sons of the same father.  Half a year has passed, and it is spring.  Genevieve reads to her father, the ancient Arkel, a letter sent by Golaud to Pelleas.  After recounting the circumstances of his meeting with Melisande, Golaud continues:  “It is now six months since I married her, and I know as little of her past as on the day we met.  Meanwhile, dear Pelleas, you whom I love more than a brother, ... make ready for our return.  I know that my mother will gladly pardon me; but I dread the King, in spite of all his kindness.  If, however, he will consent to receive her as if she were his own daughter, light a lamp at the summit of the tower overlooking the sea, upon the third night after you receive this letter.  I shall be able to see it from our vessel.  If I see no light, I shall pass on and shall return no more.”  They decide to receive Golaud and his child-bride, although the marriage has prevented a union which, for political reasons, Arkel had arranged for his grandson.