**Disclaimer: This article contains spoilers for the Long Bright River finale. Reader discretion is advised.**
Peacock's latest mystery thriller, Long Bright River, dropped all its episodes on March 13, 2025.
The show stars Amanda Seyfried as Mickey, a police officer who encounters a series of murders involving women, all of whom were s*x workers. Mickey becomes personally invested in the case because everyone, including her partner Eddie Lafferty, suspects that the murders were a result of opioid overdose, a theory she does not believe.
The killer's identity is finally revealed in the finale episode of Long Bright River. It turns out the killer is Mickey's partner and colleague, Eddie Lafferty.
More on Long Bright River ending in our story.
Long Bright River ending: The serial killer's identity explained
While Mickey hit a few dead ends before reaching the actual serial killer in Long Bright River, she finally nabs the killer in the finale, and it is her partner Eddie Lafferty.
When Kacey interrogates one of the escaped victims, Emily, she tells her that the killer is one of Mickey's partners, which she mistakenly thinks is Truman. When she delivers this news to Mickey, she is sure that Truman cannot kill four women and eventually realizes that Emily is talking about her current partner, Eddie.
Mickey was cross with Eddie throughout Long Bright River because of his attitude towards the dead women. While he was a little adamant on proving that the deaths were a result of an opioid overdose, he also did not see them in a humane way, which drove Mickey mad.
In addition, Laura's report had already deduced that the serial killer was a police officer, and Eddie's behavior throughout the investigation, coupled with the many insulin shots he kept at his home, made Mickey realize that he was the serial killer.
What happened with Eddie Lafferty in Long Bright River finale?
After realizing that her partner, Eddie, is the killer of the four women, she rushes to confront him. In an abandoned church, she finally meets Eddie to find out his motives behind killing the women.
He reveals that he was lonely and wanted some company, which is why he frequented the s*x worker community and often interacted with Taylor, Amelia, Elizabeth, and Laura. He also used the power of his badge to extract s*xual favors from the women, which soon got out of hand.
He says that the women finally retaliated against him and threatened to report him to his superiors. He had no choice but to silence all the four women and so he went on a killing spree and murdered them one by one.
Disgusted after his confession, while Mickey advanced to end Eddie's life, Kacey and his other victims opened fire on him. Mickey takes the last fatal shot and kills Eddie Lafferty.
Did Mickey and Kacey reconcile in Long Bright River finale?
While the show was majorly a murder-mystery series, the fraught relationship between Mickey and Kacey was also central to it. When Mickey comes across a series of female murders that are linked to opioids, she is worried about her estranged sister, who is also an addict.
Mickey finally discovers that Kacey is alive, safe, and living with their father. The history of the estranged sisters finally comes to light, and we learn that Mickey got away from her sister because of her ex-boyfriend Simon. He gaslighted Mickey into thinking she is superior and even got Kacey pregnant with his child, which put a wedge between the sisters.
A key information about their past is also revealed when the viewers learn that Thomas is Kacey's son with Simon. Mickey felt that Kacey was not fit to be a mother, so she took Thomas away from him.
In the finale, Mickey finally realizes her past mistakes and that Kacey has been sober, and the two sisters reconcile. She also helps her sister deliver a baby girl, and it is implied that they will now live together with their father and the two children.
Also Read: Edge of Tomorrow ending explained: What happens to William Cage?
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