The One Chicago franchise has had many characters come and go, a veritable revolving door of doctors, firefighters, and police detectives that have all made their mark, to varying degrees.
In-universe, reasons why characters leave range from medical issues, to promotions elsewhere, to family decisions, or, in the most tragic of cases, to death. Off-screen, those reasons are far less tragic, with actors wanting to explore the world outside the One Chicago franchise, salary disputes, and more. Some are expected, as is the case with Carver (Jake Lockett) on Chicago Fire, but some are seemingly inexplicable, as is the case with Sophia Bush’s Erin Lindsay, the fan-favorite character who left after four seasons on Chicago P.D. Only in Bush’s case, there is an explanation… and it’s not pretty.
Sophia Bush Had a Memorable Run as Detective Erin Lindsay on 'Chicago P.D.'
Sophia Bush describes Erin Lindsay as having "come from the street, so she already knows how all these people work." It's an element of the character that makes her stand out, and, in the hands of a talented actor like Bush, is given depth. We first meet Lindsay and the rest of the Intelligence Unit in the first episode, "Stepping Stone," but come to learn more about her history prior to joining the CPD. Her troubled childhood led to Lindsay engaging in street crime at the age of 15, but her activities brought her into contact with Voight (Jason Beghe). The meeting would prove to be life-changing, with Voight first making her his confidential informant to keep her out of jail. Before long, he and his wife took her in, giving Lindsay the affectionate, caring family that she never had growing up. That instilled a deep respect for Voight, and Lindsay would never do anything that would jeopardize their relationship, including having a relationship with Halstead (Jesse Lee Soffer), knowing that Voight frowns on relationships within the Intelligence Unit (or did).
In Season 1's "Now Is Always Temporary," the unit raids a brothel where Lindsay comes across a young, 17-year-old sex worker and heroin addict, Nadia DeCotis (Stella Maeve). They bring her in, where Lindsay interrogates her. As she does, Lindsay begins to see a lot of herself in DeCotis, a survivor stuck in a harsh life. That initial meeting kicks off one of the series' most engaging friendships, with DeCotis inspired to do more by Lindsay, just like how Lindsay was inspired by Voight. Lindsay helps DeCotis turn her life around, like a foster mother of sorts, and even takes her in as a roommate. DeCotis would take on the role of the Intelligence Unit's Administrative Assistant in Season 2, with the ambition to join her mentor on the unit. That dream was cut short when DeCotis was brutally killed in "The Number of Rats," with Lindsay there when her body is located in a crossover episode with Law & Order: SVU, titled "Daydream Believer."
The death hit Lindsay hard, sending her into a spiral downward that would take months to recover from. Another death, that of Voight's son, would shatter her world as well, but not in the same way. In "Start Digging," Voight finds the man responsible and takes him to the Silos, where he intends to exact justice. Lindsay tracks him down, pleading with him not to go down that path, but is torn between physically stopping Voight, or letting him get justice for his son. In the end, she walks away, with the sound of a gunshot confirming that Voight went through with it. Voight had, in one act, destroyed the respect Lindsay had for him. But she gets sucked into the moral decay that pervades the unit, pulling a Voight move on a suspect by sticking her gun down his throat to force information about the location of a missing girl in "Army of One." With Internal Affairs now after her in the Season 4 finale, Voight arranges for her to be recruited into a New York narcotics unit, bringing one of Chicago P.D.'s strongest seasons and strongest relationships to an end.
Sophia Bush Ends Her 'Chicago P.D.' Time on a Sour Note
Lindsay was mentioned a few times early on in Season 5, but since then there has been nothing. It's a shame, really, with Bush nailing the character's ups and downs deftly. She was strong yet fragile, hopeful yet despondent. The parent/child relationship with Voight that developed over those first four seasons played a key role in how the show approached both characters, with Voight's need to protect her, and Lindsay's respect towards him, bringing a level of raw emotion that hasn't really been matched since. In fact, it's the strengths of both Bush and Beghe to bring that relationship alive that ultimately brought their heartrending parting real gravitas.
So, why did Bush leave a role on Chicago P.D. that played to her strengths as an actress? Initially, she claimed in a 2017 Instagram post that it “took me a long time and a lot of hard work to get out of that show. Please don’t demean my capabilities by degrading my position. I left because I wanted to. End of story.” Only it wasn't the end of the story, with Bush revealing years later that she left the show after claims of abusive behavior on set. Specifically, it was the on-set behavior of co-star Beghe, whose strong relationship with Bush on-screen was the polar opposite of their relationship off of it. The claim prompted NBC to launch an investigation into Beghe's "ongoing anger management issues." Beghe would issue a public apology for his behavior, seemingly good enough for NBC to keep him on the show, which is now heading into its 13th Season.
As far as Bush was concerned, it was too little, too late. She had already moved on, taking small roles here and there before landing the lead role in 2022's Good Sam, followed up by a recurring role in the long-running Grey's Anatomy as Dr. Cass Beckman. And while she may have the time to reappear on Chicago P.D., given the nature in which she left the show, it's highly unlikely she ever will.
All episodes of Chicago P.D. are available on Hulu in the U.S.