Roque , 28 years old from Fuencarral , Madrid is in a limit situation only a year after winning the world record and the gold medal in the 100 meters freestyle at the 2020 Tokyo Olympics . His life seems to be ruined and he is desperate. As he finishes yet another day of training, he recalls the letter he has always wanted to write underwater.

Nico wants to become independent with his neighborhood colleague, Raca, but she doesn't want ties. Fed up with his parents, Nico leaves home and rents a room on the outskirts. Despite the distance, he begins to hang out with Leo, Raca's little brother, a boy who is getting hormones, because he wants to transition into a woman. Nico is torn between the love of his brother or his sister. Meanwhile, their respective families fall apart, because in one there is no love nor in the other fidelity.