Eyes of Undertow is the expression with which Bentinho describes Capitu's eyes in chapter XXXII, recalling the afternoon when, at fifteen, he gazed at her for a long time while she combed her hair. Undertow is the force of the sea that pulls inward: he says her eyes carried "a force that drew inward, like the wave that retreats from the beach on days of undertow," and that the wave coming out of her pupils seemed to want to envelop him and swallow him. At that moment, the image expresses the fascination of an enamored youth.
The other famous image, that of "oblique and dissembling gypsy" eyes, is José Dias's, who pronounces it at the Passeio Público, in chapter XXV, while speaking ill of Capitu's family. A few minutes later, on hearing Bentinho's plea for help, he changes position and proposes that the young man study in Europe, which fulfills an old ambition of the dependent himself.
The image of the sea returns at Escobar's wake, in chapter CXXIII, when Capitu's eyes gaze at the dead man "like the wave of the sea out there, as if it wanted to swallow the morning swimmer too." And in the last chapter old Bentinho puts the two together as if they were a fixed trait of hers. The book, however, shows that they were born in different mouths, on different days and for different reasons, and in chapter L the narrator himself writes that her eyes, that day, "were neither oblique nor of undertow."