Franco is a minor officer who is unexpectedly confronted by Lorenzo, a half-brother with a high IQ. Lorenzo helps him investigate an apparent suicide case in which there is something more.

Franco is overwhelmed in his first job with the homicide squad. Lorenzo suggests investigating the dead man since no one claimed his body.

The producer of a quiz show is murdered. Franco takes advantage of Lorenzo's erudition to enter the channel incognito.

At a camp, Lorenzo learns about the legend of the lonely stranger. Lorenzo is excited and suggests that his companions investigate what happened.

A businessman dies. His wife's behavior is strange. Lorenzo invents a microphone and they manage to listen to conversations, which helps them connect the dots.

A sniper kills three victims in different places. In the middle of the investigation, an inspector appears to assess how Lorenzo lived. Mansilla "hires" Marcelita to pretend to be Franco's girlfriend, thus covering up the mother's presence in the home.

The Montero brothers went to see a play. During the play, the main character is murdered and the culprit appears to be one of his fellow actors.

A businessman is found dead in a pile of sand in the middle of a construction site, with a bullet in his back. Meanwhile, Lorenzo suffers rejection from the other kids in the neighborhood.

Deputy Commissioner Serrano is involved in a "mafia" of commissioners. Franco witnesses an assault on the deputy commissioner that ends with a gunshot wound that leaves him as the main suspect.

Franco is offered the position of deputy commissioner, which he accepts. At the same time, Lorenzo receives a scholarship in a program for brilliant minds that is being developed in France. Both will have to consider and deal with big changes, which could separate them.