Plot summary

Mexico, 1673Two young boys present their mother (Marisol Ramirez) with a pendant, which she says she will cherish forever. She and her husband hold hands with their sons and dance, until the youngest boy opens his eyes and sees that everyone is gone. He walks around calling for his mother and brother, only to find the woman drowning his brother in the river. The little boy runs, only to be grabbed by his mother and taken to the river as well.Los Angeles, 1973Social worker Anna Tate-Garcia (Linda Cardellini) is getting her kids Chris (Roman Christou) and Sam (Jaynee-Lynne Kinchen) ready for school, but they miss the bus. At work, Anna overhears her boss ask co-worker Donna (Irene Keng) to check on the home of Patricia Alvarez (Patricia Velasquez), a mother with two boys, Tomas (Aiden Lewandowski) and Carlos (Oliver Alexander). Anna is their caseworker, and she hears that the boys have been missing from school. Anna convinces her boss to let her go to check on them since she knows them more personally.Anna goes to the Alvarez home with Officer Claro (Paul Rodriguez). Patricia tries to keep them from entering, but she is forced to let them in. Patricia mentions that she has been hearing the sound of a woman crying. Anna goes by a closet where she realizes the boys are being kept, but Patricia attacks Anna in an attempt to keep her from opening it. Claro pulls Patricia off Anna, and she opens the door to find Tomas and Carlos inside. They are brought to a nearby hospital where they have burn marks on their wrists.At home, Anna tries to spend time with her kids. She is a widow, as her husband was killed in the line of duty, and it has been hard on her.Later that night, Carlos is woken up by what sounds like a woman sobbing. He tries to wake up Tomas, but he doesn't hear. A guard checks in on them, and when he leaves, Tomas is out of his bed. Carlos follows him outside into the hallway. Tomas turns around and points to something in the mirror. When Carlos turns around, he sees tears dripping onto the floor before he looks up and is face-to-face with... LA LLORONA.Anna is called by Detective Cooper (Sean Patrick Thomas) to go by the hospital, leaving Chris and Sam in the car. Tomas and Carlos's bodies were found in the river. Patricia is there, wailing in despair and blaming Anna for causing her childrens' deaths, as she was trying to protect them from La Llorona. Meanwhile, Chris walks out of the car while Sam is asleep. He goes over to check on the scene, until he hears the sound of La Llorona crying. She sees him and mutters in Spanish about her children and wanting to take him. She emerges from the shadows and grabs Chris's arm, burning him. He runs back to the car and wakes Sam up. He briefly sees La Llorona's reflection in the mirror before she starts trying to roll up the car windows, but Anna comes back in time.The next day, Anna walks by the Alvarez home and sees people engaging in a sort of ritualistic cleansing to ward off bad spirits. She meets Father Perez (Tony Amendola), who explains to Anna what is going on. She asks him about La Llorona, and Perez explains her backstory. She was considered the most beautiful woman in her village, and she met a rancher who rode into town and fell in love with her. They had two sons and lived happily until she caught him with a younger woman. In her rage, she sought to spite him by killing their sons, but after realizing what she had done, she was so consumed with grief and guilt that she drowned herself as well. Because she killed herself, she was barred from entering the afterlife.Sam walks outside by the pool with her transparent umbrella as the wind blows. When she opens it, she catches a glimpse of La Llorona. The wind blows the umbrella out of Sam's hands and lands in the pool. When she reaches for it, La Llorona appears and grabs her arm, burning her as well.Anna goes to talk to Patricia in prison. She still angrily believes that Anna caused her boys' deaths. Patricia asks Anna if they have heard La Llorona crying and if they felt the sting of her tears. She admits that she didn't pray to God for the salvation of her boys, but she prayed to La Llorona to take Anna's kids in exchange for her own.Cooper and Donna show up to Anna's house that night when they suspect something is up with the kids, especially with the burns on their arms. The kids lie and say that they fell. After they leave, Anna goes to put the kids to bed. She hears a noise in the darkness and also sees La Llorona, causing her to scream. The kids enter the room after she disappears, and Anna invites the kids to sleep in her room.Later, Anna asks Chris about what has been happening. He tells her he heard La Llorona in Sam's room. Upstairs, Sam is taking a bath when La LLorona attempts to drown her. Anna and Chris hear the commotion and go to save her. As they pull Sam out of the tub, La Llorona grabs Anna's arm and burns her too as Anna sees her horrible face with her bloody tears.Anna goes to the church to ask Perez for help. He says he did not believe in the supernatural until his run-in with a certain doll (Annabelle), but he knows of a former priest named Rafael Olvera (Raymond Cruz) that can help. Anna brings the kids to Rafael's shop to ask for help. Although he appears not interested, he agrees when Sam asks for his help. Rafael goes to their home and uses eggs to determine that there is indeed a powerfully evil entity haunting them. It would not matter where they go, as La Llorona would follow them.Rafael stays with the family at night as they try to find a way to keep La Llorona out. He shows Anna that he had collected La Llorona's tears to use as anti-venom. She then appears and throws Anna against the wall before going after Chris and Sam. As La Llorona pulls Chris out the door, Rafael grabs him and throws her own tears back at her to burn her and send her out the door. He then spreads seeds from a special tree across the doorway to prevent La Llorona from re-entering. However, Chris points out that she will try to get in through the back door. As they run to the back, Sam realizes she left her doll outside. She tries to reach for it without stepping foot outside the house and without breaking the seed line. As she pulls the doll back inside, the doll breaks the line, and La Llorona pulls her outside. Anna realizes La Llorona will try to drown Sam, so they run to the pool. She jumps in to get Sam, but La Llorona starts attacking her. Rafael then blesses the pool to turn the water holy and force La Llorona out of there. Anna emerges with Sam and La Llorona's pendant.A pounding sound is heard at the door. Patricia shows up with a gun, hellbent on delivering Anna's kids to the demon. La Llorona reappears in the house, so Chris and Sam run to the attic to hide. Their attempt to keep her out fails, and she makes her way upstairs. Chris pulls out the pendant that he took from his mom and shows it to La Llorona. For a brief moment, she appears as her former human self and approaches Chris and Sam. Sam then accidentally unveils a mirror, causing La Llorona to see her hideous demonic reflection and wail. Patricia has a change of heart and lets Anna and Rafael run up to the attic to fight La Llorona. Rafael attempts to hold her off with his cross, but she throws him back. Anna runs to protect her kids, and as La Llorona approaches, Rafael throws Anna the cross. She uses it to impale La Llorona through the chest, causing the evil spirit to be finally destroyed.In the morning, Rafael bids the family farewell. As Chris and Sam run back into the house to play, Anna turns around and sees what looks like a puddle of tears on the sidewalk.