Eduardo Quintana's life lost all meaning when his wife and daughter were killed. The once renowned painter wallows in grief, subsisting on alcohol and drugs. But when a grieving mother asks Eduardo to paint a portrait of the man who killed her son, he finds himself drawn to the unusual commission. As Eduardo sets out to discover what it takes to know a killer, he is pulled deeper and deeper into Madrid's criminal underworld, where mercenaries, prostitutes, murderers, and thieves are all entangled in a dangerous and deadly web, in which nothing, and no one, are as they seem.