The Invisible Girl

Seventeen-year-old Julia is enjoying Cárdena's local festivities with her friends while her classmate Aurora has a secret date. The next day, a body appears at the high school. Julia's father Miguel Ángel is the Civil Guard lieutenant in charge of the case, but Julia also starts a parallel investigation in secret. Everybody is a suspect, and Julia discovers something disturbing.

The press is already talking about "The Compass Killer" due to one of the objects found next to the body. The police question the victim's friends and relatives and arrest the primary suspect. However, they can't find conclusive evidence. Julia continues her investigation, and someone blackmails her friend Patri. Julia's handsome classmate Iván is called in for questioning, and he asks for Julia's help in confirming his alibi. Will she do it?

While some people don't attend Aurora's funeral, a few of the mourners behave oddly at the ceremony. The interrogations continue, but the murder weapon has yet to appear. Patri is starting to get more anxious. Iván tells Julia his version of the events as well as an important secret. Someone sends Julia a riddle written on a chessboard. Can Julia prevent what's about to happen?

The serial killer hypothesis gains traction as a second body appears on the streets of Cárdena. There's a vigil for both deaths. The police continue their investigation and find new clues. Julia discovers the riddle she's been sent is an acrostic, and she deciphers a disturbing message, I know who killed her.

A traditional competition is held in Cárdena where several male pigeons are set loose after a female to breed. Some of the objects found next to Aurora's body belong to teachers from the high school, and this creates tension in the town. Julia discovers the riddle is based on a famous chess match, and Miguel Ángel leaks a bit of false news to make the killer nervous.

In despair, the town decides to organize a procession of the Virgin Mary to invoke her protection, but a third body appears. Miguel Ángel discovers several secrets that are relevant to the investigation. Julia solves the chess riddle and surprisingly unmasks the person behind the fake profile. Could they really be the murderer?

Julia and her friends unmask Patri's stalker, and the police discover he was spying on other girls as well. The case seems closed until they check his alibi. It turns out he didn't kill Aurora. So who is the murderer? Vanesa and Ingrid catch Julia and Iván together. Out of spite, Ingrid reveals that Julia lied about Iván's alibi. He was at the crime scene the night Aurora was killed.

Julia feels confused, doesn't trust anyone and needs to find out who the killer is. She searches on social media and pores over all the pictures and videos she can find from the local festivities. She has a hunch and decides to set a trap for the suspect. Meanwhile, Miguel Ángel finds something that might lead him to solve the case. But Julia gets ahead of him and is about to expose the killer, putting her life at risk.