The Vanishing Triangle

After reporter Lisa Wallace publishes an article on her mother's murder, the killer resurfaces hinting at a kidnapping. Lisa and Detective David Burkely start investigating, connecting the killer to the disappearance of a woman named Amy Reynolds.

Lisa's article is leaked, criticising the Gardaí for not acting on Amy's disappearance. David and Detective Brennan chase a lead, Mark Bulger, in Castlemoy. Impatient with the police's pace, Lisa risks her life to uncover what Bulger is hiding.

David tries to get a statement from Teresa and a confession from Bulger, whilst Lisa investigates if Bulger could be the killer. Susan pleas for information from the Gardaí when an anonymous caller claims to have information on Amy.

Lisa has to choose who to save: Susan or Mandy? Chris learns new information that takes Lisa to a strange address, where she discovers incriminating information that someone tries to cover up. The killer calls later that evening for Lisa's decision.

David and Brennan target Gough as the potential killer whilst Lisa tries to connect him to the kidnappings. Gill threatens to blackmail David if he continues his investigation of Gough. Lisa faces her worst fear with a hospital call about her father.

The investigation is halted. David confronts Gardaí's top officials to expose Gill and Gough but finds no support. He reveals a long-hidden secret to his family. Lisa and Brennan follow a lead on the killer, investigating an abandoned slaughterhouse.