When Isak shares memories of his childhood disappearance in grief therapy, therapist Vera recognizes parallels to her own past, where her brother vanished 20 years earlier.
While Isak disappears, Vera goes to her childhood home in Reftinge and tells her father and brother about her suspicions that Billy might be alive. At her dad's birthday party, she meets her uncle and realizes that she herself lied to the police.
Vera go to the site where Billy was allegedly held captive; Vera unexpectedly meets Isak again and they together look for answers to who he actually is; Mattias tries to dismiss the theory that Isak is Billy with the help of a DNA test.
In 1984, Billy goes missing and police chief Månsson leaves no resources to track him down. However, Reftinge's strongman, Harald, has his own idea of how to locate Billy.
When Vera helps Isak remember his childhood, she discovers an alternate explanation for what might have happened to Billy; Mattias decides to assist Harald in tracing Isak's identity.
Vera realizes that she never understood what was really going on when she was a child. Together, she and Mattias try to solve the mystery surrounding Billy's disappearance.
