Extremely stressed and burdened, LAPD officer Joe Baylor is navigating the intense night shift at a 911 call center besieged by numerous calls regarding a major wildfire raging in the Hollywood Hills. Having been under scrutiny following an unspecified incident that occurred during his duty eight months ago, he is anxiously waiting for a hearing that could determine his future on the force. Beside managing the chaotic flood of emergency calls, Joe is also hounded by a reporter from the Los Angeles Times, eager to extract a statement concerning the upcoming hearing.
In a critical moment, Emily Lighton, a young woman in distress, contacts the 911 line but struggles to openly communicate her situation. Joe’s instincts kick in, leading him to deduce that she is being kidnapped and is currently trapped in a vehicle with her abductor. After ascertaining that they are in a white van cruising along the freeway, the driver becomes suspicious, forcing Emily to hang up before revealing any further details. Despite Joe's quick intervention relaying crucial findings to the CHP, they face challenges in locating the vehicle without additional information. Determined, Joe makes a call to Emily's home where he connects with her young daughter, Abby. Abby discloses alarming information about her mother being taken by her ex-husband, Henry Fisher.
In an effort to gather more information, Joe acquires Henry's phone number from Abby and uses it to track down the van's license plate number. He promptly passes this vital information to the CHP and dispatches a LAPD patrol car to check on Abby and her baby brother, Oliver. However, his attempt to search Henry's apartment is thwarted due to a lack of a warrant.
Seeking to reach out to his estranged wife Jess, with whom he has been separated for six months, Joe attempts to talk to their daughter Paige. Yet Jess is unwilling to attend the hearing and firmly requests Joe to cease his calls. In a desperate attempt to confront Henry, a man with a troubling history of violence, Joe reaches out but after a tense exchange, Henry hangs up on him. Joe's next call is to his former partner, Rick, who is on his day off. He urges Rick to investigate Henry's residence. Rick, who is supposed to testify at Joe's hearing, expresses unease about the potential outcome, citing interactions with federal agents.
Things escalate as Joe receives a frantic call from Abby, persuading her to allow two LAPD officers performing a wellness check into their home. The officers discover Abby distraught, with blood on her hands and startlingly, her brother Oliver - who she claimed was only "sleeping" - is found gravely injured. In an urgent turn of events, Rick breaks into Henry's apartment, uncovering piles of letters and documents. During another tense phone call with Emily, Joe desperately convinces her to attempt to pull the handbrake as an escape maneuver, but it fails to halt the van’s progress. A following call reveals that she is trapped in the back of the vehicle, panicking over Oliver's condition; she reveals disarmingly troubling thoughts about her son having "snakes in his stomach."
As tension mounts, Emily manages to strike Henry with a brick during a fiercely desperate attempt to escape. Subsequently, Rick contacts Joe, informing him of papers he discovered at Henry's apartment linked to a psychiatric treatment facility in San Bernardino where Emily had been a patient before. As the dire details unfold, Joe learns that Henry had been returning Emily to the facility due to their inability to afford her medication.
The gravity of the situation escalates further when Emily reaches out again, disclosing a heart-wrenching intent to jump from an overpass, believing she can't face the consequences of what she has done. Joe, in a bid to save her, directs the CHP to her location while delicately talking her down from her perilous decision. He shares a personal, painful truth with her, > "I killed a man while on active duty." This confession becomes a pivotal moment as he affirms that he did it while grappling with anger; a sentiment that resonates deeply with Emily. His heartfelt reassurance that her family still loves her and that Abby needs her, alongside his promise she would return home, becomes a lifeline in her darkest moment.
Just when Joe fears the worst, the CHP notifies him that they managed to persuade Emily to come down safely. Furthermore, it is a relief to learn that Oliver is alive and receiving treatment in the ICU. Overcome with emotion, Joe retreats to the restroom where he is overwhelmed and sickened by the entire ordeal. He promptly contacts Rick, imploring him to retract his previous statement and tell the truth during the upcoming trial, even if it means facing years behind bars. Finally, Joe reaches out to the L.A. Times reporter, resolutely informing them of his intention to plead guilty to manslaughter in court.
