Verónica León is an inspector of Homicides in Madrid. For the last couple of years she has been in a somewhat tortuous relationship with sub-inspector Roberto Vidal, who separated from his wife around the same time. During one of their occasional meetings, they are told that an old man has been murdered. On arriving there, the widow's behaviour makes them focus their suspicions on her, although they find certain elements that just don't fit. A second victim appears the following day: an elderly woman who has been hung from her window by a rope tied around her neck, making it seem like suicide. Although there seems to be no relationship with the first victim, they find details which make them think that the two crimes are related.