The film commences with Ashley Radcliff (Storm Reid) calling her detective uncle Jack (David Oyelowo) to rescue her from the movies after her father forgets to pick her up and her mother is preoccupied. Jack responds promptly, taking her to a diner where they enjoy a meal together. Amid their conversation, they discuss Ashley's father, Garret (Brian Tyree Henry), an aspiring musician turned drug dealer, whom both Jack and Ashley view as a failure. Determined to help, Jack vows to get Garret back on track.
The following day, Jack receives a phone call from Ashley, who reports that Garret seems to be making an effort to improve his life after Jack’s stern talking-to about his neglectful behavior. However, the situation takes a dark turn when hours later, Jack receives a distressing call from Ashley that compels him to rush to their house, only to discover an unimaginable tragedy: Garret is dead, his wife Susan (Shinelle Azoroh) lies in a pool of her own blood, and their dog Wilco has also succumbed. The horror escalates when Jack finds Ashley dead in the shower, leading authorities to rule the incident as a murder-suicide. Jack is left feeling burdened with guilt, believing his harsh words to Garret may have influenced this devastating outcome, although he is supported through this trauma by his partner, Bobby (Mykelti Williamson).
As two weeks pass, Jack remains haunted by the events. He receives a perplexing phone call from Ashley's number, which leads him to check the evidence room only to discover her phone there, ruling out any prank. Seized by a mix of desperation and hope, he returns to Garret's house and hears what appears to be Ashley's voice. Jack is gripped by disbelief as he realizes she is attempting to communicate from beyond.
Jack soon finds himself under scrutiny as Internal Affairs, represented by agent Roger Lee (Byron Mann), begins to question his potential involvement in his family's deaths. During their interview, they inquire about any motive he might have had to eliminate his loved ones, suggesting a possible attraction to Susan. The bewilderment increases when Ashley calls again, echoing their last conversation before the murders, prompting Jack to direct her towards a shed outside and instruct her to mark it with a large red X, which she dutifully does. To his astonishment, Jack finds the marked X later, realizing Ashley is somehow reaching out from the past.
Jack's obsessive quest for answers leads him to meticulously sift through case files and crime scene photographs, hoping to uncover critical clues to prevent the tragic fate of his family. This behavior raises alarm for his boss, Howard (Alfred Molina), who urges Jack to step back from the case. Meanwhile, Ashley, still in the past, investigates her father’s activities, discovering a name—Georgie—associated with the dangerous world of crime. When Jack discusses this with Howard, he learns that Georgie is a notorious figure who remains elusive and is suspected of having ties to Garret's demise.
As their communication continues, Ashley reveals she has found her father’s day planner, which contains Georgie's address. Acting on this revelation, Jack warns her to turn back for her safety, yet the peril is closing in. In a hair-raising incident, he becomes a target himself, and after a gunshot wound, he implores Ashley to contact the police, giving her Bobby's number as a source of support.
Frustration and confusion mount as Ashley confronts Jack about his intentions, believing he is hiding important truths from her. The stakes escalate when she experiences another terrifying time flash, and tragedy strikes again as she finds herself trapped and unable to escape a doomed fate.
In the present, Jack prepares for an inevitable confrontation while revisiting memories of Ashley before her demise. He reconnects with her just as she flees on her bike, pursued by danger, leading to a desperate attempt to protect her from the shadow of Georgie's associates. The revelation of Bobby’s betrayal emerges, unraveling a thread of deceit deeply woven into their lives. As Jack's timeline hangs in the balance, he is faced with impossible choices to save Ashley, unraveling the threads of fate that threaten their very existence. Ultimately, Jack's courage paves the way for a new path, offering solace as he comforts Ashley, who is freed from the chains of a dark reality.
