The flapping of a butterfly's wings splits Romina's destiny into two parallel, alternating timelines. In one, Romina is abandoned by her biological mother and raised by another family, becoming involved with her brother, German, in a relationship where mutual desire is forbidden. In the other timeline, Romina is not abandoned by her biological mother and meets German by chance, opening up the possibility of a permissible relationship that, for some reason, fails to materialize.