Julián is standing on the street, and watches how his past self holds onto a dying Maite, while a mysterious stranger stands next to him. It turns out to be a dream when he wakes up.
Alonso goes to the past, and watches his wife Blanca from afar: she shows obvious signs of being abused.
Amelia goes to the cemetery, and visits her tomb... and that of her daughter.
Several months have passed since Leiva's attack and death. And now, Salvador has a new mission for the patrol. Irene has returned from her holidays to coordinate the mission. Ernesto feels some doubts about her and her potential relation with Leiva's escape, as she was the last one to meet with the man and gave him pills that might well have been what allowed him to fake his death. However, Salvador fully trusts Irene, and tells so to Ernesto, as he reflects on the fact that it is his wedding anniversary, but he does not intend to go to the past to see her.
The team reunited in the Ministry, Salvador shows them a poster created by Salvador Dalí in 1924 for the theatrical version of Don Juan Tenorio organized by the Residencia de Estudiantes
. It seems to be normal, but there is one surprising detail: a tablet has found its way to the poster. Seeing this as a potentially serious breach of the Masquerade, the trio must go to that year and find out why that happened. On their way to their door, they encounter Velázquez (who is going to the past to meet fellow painter Francisco de Goya) and Jordi Hurtado (memetically famous because he is believed to be The Ageless), fellow agent who uses the time doors to film episodes of his quiz show.
When they arrive to the Residencia, they meet a cavalcade of men and women who will become famous artists in the future, among them Salvador Dalí, Luis Buñuel (who Julián states is the greatest Spanish director in history) and poet Federico García Lorca... who not only is identical to the stranger Julián met in his dream, but also recognizes him, much to Julián's surprise.
Going through their investigation in the backdrop of the rehearsals for Don Juan Tenorio - with much clash between the personalities of all the actors and the play director, Pepín Bello - yields nothing, but Alonso finds an envelope with the Ministry's seal. Within, he finds a photograph and a message: the photograph shows Julian and Amelia's wedding in 1883, and the note states "Beware the future".
Back in the Ministry, Alonso shows his partners the photograph. They reveal how Julián played Amelia's boyfriend during the mission to save Rabbi Leví to allay Amelia's parents suspicions. This leads them to consider that the mission might be a trap of some kind. Amelia seems to be quite affected, and Julián tells her that he loves her like a friend, and that they probably just married as a front. Amelia, though, does not seem so convinced: it is clear that she may actually be in love with her partner.
No matter what, the mission must continue, and the patrol returns to 1924, intending to find both who is behind the poster and the photographs. Lorca meets Julián apart from the others in the group, and asks him if he comes from the future: somehow, Lorca has the ability of dreaming about the future, which has influenced part of his work, such as the poem he wrote in 1930 where he could have prophecized his own death. The two men speak and hug each other, something that is witnessed by Silvia, a student that lives in the Residencia.
Amelia finds Silvia crying her eyes out, and the latter reveals that she likes Julián, but after seeing him with Lorca, she thinks he is homosexual. A little conversation later, Amelia reveals her full name and Silvia thinks it is a bit funny, because her grandmother was called exactly the same. Amelia realizes, with some horror, that Silvia is her granddaughter... and might be Julián's too.
The family drama is cut short, though, when Lola Mendieta appears in the scene: she has been hiring Dalí to make paintings so that she can sell them later at very high prices. As they think about the possibility that Lola is the one behind the photograph, Alonso and Julián find two more photographs, these showing their respective wives, dead, and a message saying "You can stop it". This throws the team off, putting the mission in risk.
However, Lola sends Amelia a message so they can meet. Lola then tells the younger woman that, yes, she is the one behind the situation with Dalí, but denies being the one that is sending them the photographs, because, for her, the enemy is the Ministry, not its workers. This time, though, Lola does not get to escape: she is swiftly captured and sent to the 1053 prison.
The culprit behind the photographs is revealed to be Irene: she wanted to take some misguided revenge on the patrol, for their role in leading to Leiva's death, and so, when she found out about Lola's dealings, she did not mention them so she could use it for her own benefit. Salvador sends Irene to the psychiatric hospital, so she can get back on her feet, and reveals to Ernesto he was the one who gave Leiva the drugs he used to fake his death.
Alonso decides to go to 1570, with the objective of preventing his wife's death at the hands of the man she married after Alonso's "death". He succeeds in scaring the man into treating Blanca as she deserves, using what he remembers from seeing the rehearsals, but is not able to leave before Blanca appears. He ends up telling her he has been allowed to return as her guardian angel just this once to protect her, and that he can become corporeal for a few moments. Blanca hugs him, and thanks him for what he has done.
In the present, though, Julián is about to set on a risky idea. Angry because he cannot tell Lorca he is going to be killed in 1936, he has decided to travel to the year 2012 to save Maite from being run over. Amelia, after finding another photograph, decides to go help him, even though she knows it is against the rules.
Both of them take a car, and Julián rushes to the place where he knows Maite will die. When he arrives, though, he causes a chain of events that ends up with Maite dying. Without knowing it, Julián has caused the accident that killed his wife and prompted him to go back to the past to stop it. Amelia manages to talk him back to his senses before 2012!Julián arrives in his ambulance - only to have Maite die in his arms.
Back to the present, Julián laments what he caused and Amelia tries to console him, but he rages about it, the Ministry and tells Amelia that there's no chance of them getting together ever. As he closes the door to his room rather forcefully, Amelia gets the photograph out and gazes on it: it shows Julián, herself and a young baby girl, smiling. A crying Amelia rips the photo off.
