In the third episode of Deadloch, as Cath ventures into artistic pursuits, she stumbles upon a corpse by a lake. Simultaneously, Redcliffe is discovered by Tammy and Miranda in an underground pit. Dulcie rushes to the scene where Cath found the body and requests James to examine it as soon as he arrives. James observes that the body is afflicted with Sapnofied, a term for bacterial decomposition in a moist environment. Upon closer inspection, Dulcie identifies the corpse as Sam O’Dwyer’s. Redcliffe enters and recounts her encounter with the deceased, and Dulcie informs her of the new discovery. Their opinions diverge significantly.
Redcliffe recognizes Jimmy when she returns to the police station, believing him to be the person she had been chasing the night before. She gives chase, only to find Phil patiently waiting. Redcliffe suspects Phil to be one of the main suspects, whereas he speaks to the local news expressing his discontent with the town’s handling of the murders.
The employees at the dock dispose of Sam O’Dwyer’s boat’s trash. Abbie notices a bloodstain and requests the detectives to test its DNA. Redcliffe rushes to the pub to find Phil’s DNA, despite Dulcie’s hesitation.
Dulcie breaks the news of Sam O’Dwyer’s passing to his loved ones. Redcliffe enters the bar and retrieves a glass that may contain Phil’s DNA. Dulcie and Ted converse on the beach, and she reaches out to Hannah for the criminal profiler’s contact information.
James informs Dulcie and Redcliffe that Sam’s corpse also had its tongue removed, leading Dulcie to conclude that all murders are connected. Redcliffe, however, remains focused on linking the case to her latest suspect, Phil, despite Dulcie’s intuition suggesting otherwise.
The next day, Redcliffe orders a town-wide DNA test despite the unclear DNA report regarding Phil being the suspect. The episode weaves a complex web of intrigue and suspicion, with each character grappling with their own motivations and theories in the face of this mysterious series of murders.
As Dulcie reaches out to the criminal profiler, she's informed that the expert is actually in Deadloch, attending a festival. Her quest for Dr. Daniela Kehlman leads her to a discovery, but Daniela initially seems uninterested. However, once Dulcie reveals the details of multiple homicides over time, Daniela's attention is piqued.
Redcliffe steps in, but Dulcie continues to pour out every piece of information about the killings, many of which point towards a vicious serial killer. Redcliffe is extremely disappointed to learn that she must stay to crack the case, as it seems to be getting worse. A call from her boss Scotty doesn't go well for her, and Redcliffe goes to the neighborhood pub to drown her sorrows.
Meanwhile, Stephanie, a journalist, stops by for a nightcap and decides to interview Redcliffe for more information on the case. Dulcie tries to ask Daniela more questions about the killings but is brushed off. Mike calls Dulcie and informs her that Redcliffe has told the journalists everything there is to know about the case.
When Redcliffe and Phil McGangus leave to board the boat, Dulcie arrives at the bar. She confronts Redcliffe, accusing her of not taking the matter seriously and speaking to the media. Dulcie also warns her that she has endured enough disrespectful behavior and suggests that if she's not willing to investigate the matter, she can return to Darwin. Redcliffe reveals that nobody in the Darwin office wants her and that they believe she's just a screw-up because she wasn't present when her partner was devoured by a crocodile.
After an apology from Dulcie for confronting her in such a manner, she also warns her about the possibility of a serial killer. When Abby arrives, she asks a crucial question about the victims' lack of defensive marks. Her hypothesis states that those who died were given drugs, and the updated toxicology report proves that drugs were present within the victim's system.
This new evidence leads Dulcie to draw a new conclusion: the most recent hint suggests that the murderer is a woman because men rarely poison in cases involving serial killing. For the first time, Redcliffe agrees to back Dulcie's investigative methods as the episode comes to a close.
