The key to the tale is the death of León (whom we never see in flashback or photograph). He was in a long term relationship with Flavia, in her forties, who works in a good position as research chemist in the University. Flavia is in good relations with León's ex Mónica, who lets her continue to live in the house she shared with León; in return, Flavia helps Mónica frequently to take care of her daughter Lucía, who is in the process of beginning high school. Flavia and Lucía's relationship is polite but testy, although a moving scene shows there are true feelings from both sides.
For the rest of the movie we witness Flavia trying to rearrange her life without León. Some of the tasks are easy; medical insurance, the search for new living quarters. Others are more elusive: the quest for a meaningful relationship such as the one (we assume) she had with León, her choices dwindling steadily.
In final balance, nothing much happens on screen. We spy on the characters for a short time, then we try to guess the past and understand the motivations of people we don't entirely know or sympathize with. Excellent acting specially from Lorena Vega (Flavia). The movie is a mostly successful incursion into extreme minimalism.