Merciless (2014)

Edu is a young man above all suspicion: handsome, smart, sensitive, and a dedicated boyfriend. However, his perfect man appearance is simply a mask that covers up his fearsome personality: a dangerous psychopath, behind a number of crimes that have caught the police's attention. A cold, conniving, and callous criminal; a serial killer who kills purely out of pleasure. In order to test investigators, Edu deliberately leaves clues, and thus devises an intense mind game, a psychological thriller. It becomes a question of honor for the police taskforce to uncover the true identity of a killer and the way he commits his crimes.