Again the scene changes. Melisande and Genevieve are walking together in the gardens, and they are joined by Pelleas. “We shall have a storm to-night,” he says, “yet it is so calm now.... One might embark unwittingly and come back no more.” They watch the departure of a great ship that is leaving the port, the ship that brought Golaud and his young wife. “Why does she sail to-night?... She may be wrecked,” says Melisande.... “The night comes quickly,” observes Pelleas. A silence falls between them. “It is time to go in,” says Genevieve. “Pelleas, show the way to Melisande. I must go ’tend to little Yniold,” and she leaves them alone. “Will you let me take your hand?” says Pelleas to Melisande. Her hands are full of flowers, she responds. He will hold her arm, he says, for the road is steep. He tells her that he has had a letter from his dying friend Marcellus, summoning him to his bedside, and that he may perhaps go away on the morrow. “Oh! why do you go away?” says Melisande.
The second act begins at an old and abandoned fountain in the park—the “Fountain of the Blind,” so called because it once possessed miraculous healing powers. Pelleas and Melisande enter together. It is a stifling day, and they seek the cool tranquillity of the fountain and the shadow of the overarching trees—“One can hear the water sleep,” says Pelleas. Their talk is dangerously intimate. Melisande dips her hand in the cool water, and plays with her wedding-ring as she lies stretched along the edge of the marble basin. She throws the ring in the air and it falls into the deep water. Melisande displays agitation: “What shall we say if Golaud asks where it is?” “The truth, the truth,” replies Pelleas.
The scene changes to an apartment in the castle. Golaud lies upon a bed, with Melisande bending over him. He has been wounded while hunting. Melisande is compassionate, perhaps remorseful. She too, she confesses, is ill, unhappy, though she will not tell Golaud what it is that ails her. Her husband discovers the absence of her wedding-ring, and harshly, suspiciously, asks where it is. Melisande, confused and terrified, dissembles, and answers that she must have lost it in a grotto by the seashore, when she went there in the morning to pick shells for little Yniold. She is sure it is there. Golaud bids her go at once and search for it. She fears to go alone, and he suggests that she ask Pelleas to accompany her.
The next scene discovers Melisande with Pelleas in the grotto. They are deeply agitated. It is very dark, but Pelleas describes to her the look of the place, for, he tells her, she must be able to answer Golaud if he should question her. The moon breaks through the clouds and illumines brightly the interior, revealing three old and white-haired beggars asleep against a ledge of rock. Melisande is uneasy, and would go. They depart in silence.