Isabel, some years later, discovers something that was left undone: obscure yet frighteningly present. This presence leads her to make a strange ritual: To revisit the crater lake, at the top of a small volcano, the place where everything had happened in her inescapable relationship with Joao. There, into the centre of a circular lake, she casts the last and most beautiful love letter written by him, tied to a stone, in an attempt to put an end to this feeling, this longing mixed with madness, shadow and light. An attempt to finally return herself to herself.