A skeptical homicide detective discovers that an inmate's panicked reaction to blood is due to hematophobia and not the trauma of the crime she is accused of, so he reinvestigates the case, solving it and releasing her.

SYNOPSIS:

CRISTÓBAL DURÁN (31), a skeptical homicide detective from La Paz, Baja California Sur, receives an urgent request from his ex-girlfriend SABRINA TAMAYO (30), a brilliant systems engineer, to visit her at the prison where she is serving a sentence for the murder of her half-sister MARGOT HEREDIA (25). Cristóbal, who almost lost his promising career because of one of her lies and finds it hard to forget her, visits her. Sabrina assures him that she is innocent, although her fingerprints are the only ones on the murder weapon. She asks Cristóbal to reinvestigate the case. He, incredulous at her request, refuses. In addition, the case was conducted by ALFREDO CASTELLANOS (30), who has a high rate of solved cases. Sabrina makes the request through YVONNE PINTO (32), her lawyer and best friend.

Just as Cristóbal leaves, an inmate at another visiting table is assaulted by the visitor and bleeds. Sabrina, seeing the blood gushing out, goes into shock and needs to be subdued to calm her down. Upon witnessing Sabrina's reaction to the blood Cristóbal is sure that it is because of the memory of committing the murder.

Cristóbal talks to his forensic friend, JIRO YAMAGAWA (57), about Sabrina's reaction to the blood. Jiro mentions that it may be hematophobia. Giving Sabrina the benefit of the doubt, he investigates the case again from the angle of Sabrina's version. Out of respect for Alfredo, he tells him. This confronts them.

Cristóbal visits Sabrina. She is sexually harassed by two inmates: Berta Hiedra (36) and Carla Guerra (34). Cristóbal gets the name of PABLO CAMINO (28), Margot's unfaithful ex-boyfriend, who insisted that they get back together. Pablo tattoos the name of his conquests on his arms. In Sabrina's social networks, Cristóbal sees in a photo Sabrina, Yvonne, Margot and Pablo sharing with other people on a day at the beach. It is obvious that Sabrina does not like Pablo. Margot wears sunglasses that are disproportionately large for her face.

Cristóbal visits Yvonne. She lives with little KATE (3) in an apartment with a foyer cluttered with photos featuring a young girl he saw on Sabrina's social media. Yvonne visited Margot that day in the afternoon to mediate between the two stepsisters over a bitter argument between them the day before, which in the file is marked as the motive for the case. Yvonne left to pick up Kate at the daycare, but Margot called her minutes later by phone to continue. That was Margot's last call in life.

The young woman in the photos is CINDY (26), younger sister of Yvonne, who died years ago. Pablo is in the south of the country. Cristóbal sees resemblance between Kate and Pablo, he suspects that she is the daughter of Yvonne and him, product of one of his infidelities. Cristóbal and Alfredo have a new clash, almost physical, because of their investigation.

Sabrina is attacked by the inmates who harass her. She avoids being raped but is badly injured. The warden, fed up with the aggressors, transfers them to another prison.

Cristóbal, supported by Jiro, establishes that Sabrina's fingerprints remove the knife and do not introduce it. Her time of arrival does not coincide with the time of the murder. With the new evidence Yvonne releases Sabrina. Alfredo, uncomfortable, admits his mistake in the investigation. Cristóbal asks for his support to solve Margot's murder together. Alfredo, humbled and willing to take the opportunity to correct his mistake, accepts. Sabrina tries to reconnect with Cristóbal. Cristóbal's mind wants to push her away, but his heart brings her closer.

Alfredo is on the trail of Pablo's whereabouts and Cristóbal reviews the tapes from the day of the murder. Yvonne's white blouse is not the same when she comes in and goes out. She leaves wearing sunglasses although it was a rainy day, those ones Margot wore in the beach photo.

The body of a man found in a grave in Chiapas is identified by his tattoos. It is Pablo, he was killed in the same way Margot was. Pablo was seen with a woman resembling Sabrina shortly before his death. Alfredo talks to Cristóbal who thinks he may have ended up freeing a real murderer by believing her lies. Cristóbal sends Alfredo the photo he got from social networks to identify Sabrina, but instead of identifying Sabrina, Yvonne is the identified one. Cristóbal and Alfredo try to contact Yvonne without success.

Cristóbal reviews the file. The time of Margot's call to Yvonne coincides with the time of her death, she was unable to make the call. Yvonne's DNA was in the house and in Margot's hands. Cristóbal is struck by the fact that only a group of numbers are marked on the cell phone screen. The numbers are familiar to him. He searches his own cell phone for recent numbers and the number positions match those on Yvonne's cell phone. He searches Margot's cell phone for the history of calls to Yvonne and finds thirty-six. He finds it strange that, having her contact stored in the directory, she dialed the digits on the screen to call her with her right index finger with no evidence of holding the device in her left hand. She does a more thorough physical examination of the device, it is totally clean, except for the fingerprints on the screen. Cristóbal and Alfredo agree that Yvonne may have murdered Margot and took her finger to simulate the call. Cristóbal goes back to review the video of Yvonne's exit. The time of the call is before Yvonne left the building. She is not seen talking on the phone, but the call was active by that time. He concludes that she faked the call for her alibi, but did not consider the relationship between the times. He applies for a warrant to search her house. The police officers force Yvonne´s house front door. In the search they find Yvonne's white blouse that she wore when she entered the building on the day of Margot's murder. It is bloody. It is sent to the lab for DNA testing. The blood on Yvonne's blouse is Margot's and did not get there by transfer, but by contact. That places her at the crime scene at the time of the crime. Cristóbal requests an arrest warrant for the lawyer.

Cristóbal thinks Yvonne may be on the beach where the photo was taken and finds her there. He coordinates with the local authorities. After Cristóbal lets her know that he has discovered her, she flees and after a chase in which Yvonne puts Kate at risk, she is arrested. DNA tests establish that Pablo is Kate's father, and that Yvonne is not her mother but her aunt. Cristóbal discovers that Cindy was raped by Pablo and became pregnant and died in childbirth. Yvonne avenges her sister by murdering Margot when she confesses to her out of remorse for seeing her suffering for the loss of her sister, that Pablo raped Cindy. She then hunted Pablo down until she found him and killed him for his crime. Alfredo acknowledges Cristóbal's investigation, congratulates him and shows his respect.

Sabrina is shocked by the truth of the facts; joyful that the case was solved but devastated that the murderer is her best friend. She skillfully shows herself vulnerable to Cristóbal and they spend the night together. When he wakes up, Sabrina has already left without saying goodbye.

Yvonne is sent to the same prison where Sabrina's stalkers are, and when they see her arrive, they stalk her as well.