As the narrative of Ellis unfolds, we are introduced to the breathtaking scenery of the Peak District National Park. A man stumbles upon a vehicle partially submerged in the water, with a lifeless body concealed within its depths. A day prior, Rowan Edwards (portrayed by Daire Scully) competed in a swim meet, displaying his prowess in the water. Post-competition, Maggie Bradley (Freya Hannah-Mills) and her companion drinks gathered for a leisurely drink, their spirits high. Aaron Kelly (Conor Sanchez) urges Carrie Booth (Tallulah Evans) to gently escort Maggie from her perilous perch on a bench, fearing she might injure herself. Alas, Maggie's balance failed, leading to an unfortunate accident. The victims were last seen on Sunday at 2:30 PM, a time that now marks the beginning of a tragic mystery. Rowan's life was extinguished, and Maggie remains missing, her whereabouts a haunting enigma.
Detective Sergeant Chet Harper (Andrew Gower) converges with Detective Chief Inspector Ellis (Sharon D. Clarke) at the police station, where Ellis declines to exchange a handshake, a gesture that speaks volumes. They proceed to the incident room, with Chet revealing that Stephen Mason (Michael Wildman), the stepfather, has been brought in for questioning. Under the scrutiny of DCI Jim Belmont (Chris Reilly) and DC Kate Trent (Charlotte McCurry), Mason is grilled about his altercation with Linda, which occurred after Maggie and Rowan's departure. Mason categorically denies storming out and claims to have resided in a caravan at East Moor Caravan Park. DCI Belmont counters with evidence suggesting otherwise – footage that proves Mason's absence from the caravan site. He speculates that Mason harbored jealousy towards Rowan. Just as Mason lunges towards Belmont, Ellis bursts into the interview room, demanding the key, her demeanor fiery.
After Mason's departure, Belmont asserts control, but Ellis' intentions to claim his office ignite a fiery confrontation between the two. In the confines of their vehicle, Ellis shares her insights – Rowan was struck from behind, the telltale signs of rust embedded in his wounds pointing to an unknown assailant. Yet, no definitive evidence ties anyone to the crime. Ellis doubts Mason's involvement. Arriving at the crime scene, the car remains eerily submerged, yet Chet notes the absence of damage, with only tracks from an Audi and two partial footprints – likely left by wellies – visible. The mud in these prints doesn't align with the surrounding terrain, and similarly, traces of it adorn Rowan's jeans. Beneath the waterline, however, there are no prints or DNA clues, suggesting the car was deliberately pushed into the water.
The conversation shifts to the celebratory atmosphere post-Rowan's record-breaking swim, their phones pinging outside Hanmore before going silent. Ellis and Chet meticulously reconstruct the timeline, hypothesizing that once the car became immobile, the perpetrator likely traversed the road on foot. Ellis remains unconvinced that Maggie was in the car, clinging to the hope that she might still be alive. They deliberate on Maggie's fate, with Ellis resolute in her belief that she is not deceased, eager to converse with the victims' parents. Upon arrival, Chet receives a message from Belmont, inquisitive about Ellis' actions. Upon discovering incriminating images on Belmont's phone, he tasks Kate with summoning Harper back.
Chet and Ellis engage with Eric Mercer (Tom McKay), Rowan's uncle, whose demeanor hints at knowing more than he lets on. Michael Edwards (Wayne Foskett), Rowan's father, voices his suspicion, convinced he knows who bears responsibility for this unspeakable tragedy.
He asserts that Mason is the type who would resort to beating a child to death. Ellis confides in Louise Edwards (Catherine Walker), expressing her desire to uncover the truth about Rowan. Michael, overcome with emotion, shatters a glass, stressing that Rowan was merely a child until that fateful encounter with his killer. Privately, Louise contends that men often struggle to cope as adeptly as women do in such situations.
Ellis is presented with a photograph depicting Rowan's circle of friends, including his cousin Amy. Louise reminisces about her brother's protective nature over Rowan and everyone else during her tenure in office. Notably absent from the photo is Maggie, who refrained from swimming and wasn't at Meredale at the time. Curious, Louise inquires about the motive behind Stephen Mason's alleged murder of Rowan, to which Ellis clarifies that she hasn't accused him outright.
Outside, Chet enlightens Ellis about Eric, alias Peter Pan and the Green Man, who served as the gatekeeper when Louise was an MP. At the police station, Ellis uncovers information extracted from Mason's phone and undergoes an interrogation led by Ellis and Belmont. Mason claims Linda captured the photos after catching a television program about teenage models, using his phone due to its superior camera quality. Ellis reprimands Mason for remaining confined in the interrogation room rather than searching the hills for Maggie, questioning the veracity of his alibi about spending the night at a caravan park. Mason stands firm in his assertion.
Ellis requests Kate Trent to compile a list of crimes in and around Hanmore on the night of the incident. Meanwhile, Chet and Ellis encounter Linda Bradley (Kaye Wragg), distributing missing persons flyers for Maggie. Ellis draws Chet's attention to Charles "Carlos" Braine (Brian Markey), who isn't currently under their surveillance. Intrigued, Ellis insists on adding him to their radar. Speaking with Linda about Mason's assistance at the station, Linda learns that the Watsons have canceled their appearance for the next day, blaming Ellis and the police for causing volunteers to abandon their posts. Ellis suggests they retreat indoors for tea.
Linda confirms that she took the photos of Maggie using Mason's phone and discusses her willingness to evict Mason if she suspected he posed a threat to her child. She clarifies that their argument wasn't centered around Rowan and insists she never envisioned Rowan harming Maggie, unlike Mason who tends to anticipate the worst. Linda underscores Mason's reluctance to jeopardize his family, whom he views as his only possession.
Chet informs Ellis about a farmer's report of a trespasser in Cranbriar on the night in question and a taxi break-in on Church Street. He attempts to engage Ellis in a conversation about her daughter, but she deflects, asking him to brief her on Carlos the next day. As Ellis walks away, she sends a heartfelt message to Grace, expressing her thoughts. She then receives a call from ACC Alison Leighton (Allison Harding), who expresses concern for her wellbeing amidst the media scrutiny surrounding the case.
Ellis notices a girl conversing with Carlos from her window and conveys to Leighton her belief in Maggie's survival. Still awaiting a response from Grace, Ellis obtains CCTV footage of the taxi break-in. Chet calls, inviting her for a drink, but she politely declines, citing her workload before abruptly ending the call.
On the CCTV footage, she catches a glimpse of Rain. Subsequently, both Rain and Linda are subjected to questioning. Rain states she ventures out when the streets are serene. When inquired about the contents of her shopping bag, she firmly asserts that there was nothing remarkable inside. Ultimately, Chet confiscates her phone to monitor her whereabouts.
While riding in the car, Chet informs Ellis about Carlos, a notorious dealer. He makes a call, expressing his intention to bring in a person of interest. The duo then visits Peter Kelly (Barry O'Connor) at the swimming club, where Peter speaks glowingly of Rowan, the former captain. Peter shouts at Aaron to address the issue of arm recovery, insisting that it's a matter of determination. Aaron gives Peter a hard stare as he passes by. Peter last encountered Rowan during the meet. When Ellis mentions the celebration, Peter reveals he was dealing with Aaron.
Ellis engages with Rowan's friends. Carrie insists that the night is a hazy memory, while Maggie was more incapacitated than anyone else. Carrie emphasizes their sorrow for Maggie, but underscores that Rowan is the one who has passed away. Aaron dismisses Rowan as not belonging to their circle. After Maggie left, Amy escorted Carrie home since she doesn't drink. Aaron claims he made everyone disperse and was out by 3:30 AM, walking alone and never seeing them again.
At the police station, Trent, Ellis, and Chet scrutinize videos from the teenagers' phones. They uncover that Amy was with Rowan and Maggie but later returned, a detail Amy omitted in her statement for 20 minutes. Amy subsequently claims she was assisting Rowan in placing Maggie in the back seat. She adds that Carrie pretended to be unfazed, despite still liking Rowan. Aaron and Maggie had a heated exchange. Amy returned to the party as she promised Carrie a ride home. Eric asserts he heard Amy arrive around 3:30 AM. Chet inquiries if Rowan said anything, and Amy responds that she was with him for just a brief period.
Following the interview, Ellis instructs Trent to compile a comprehensive timeline of Rowan's week prior to his demise. Meanwhile, Ellis and Harper stumble upon Carrie and Carlos engaged in a heated argument. Carrie implores Carlos to remain silent. Edward intervenes to separate them and asks Carlos to accompany him to the police station. Seeing Carlos bolt, Ellis reverses her car and blocks his path. She exits the vehicle and opens the back door, and Carlos silently gets in. Harper notices Carrie entering Meredale School. Ellis assures him they are aware of Carrie's whereabouts.
At the station, Carlos divulges that Maggie and Rowan were frequent patrons at the pub where he works. He agrees to a search of his residence. Ellis envisions Carlos wielding something ominously before terminating the interrogation.
Ninety-three hours after Maggie vanished, Kate imparted to Ellis that Carlos' alibi had been substantiated; his girlfriend had been at home when he arrived by taxi. Belmont confronted Ellis, accusing him of advising Louise and Michael against Mason's detention. The soil sample revealed a high peat content, purportedly originating from Lower Moor, spanning an expanse of 100 square miles. Belmont contended that the police force lacked the manpower for such an extensive search and proposed mustering volunteers instead. He attributed the dwindling cooperation with the police to Ellis' public arrest of Stephen amidst the search efforts. He steadfastly maintained that there was insufficient evidence to justify Mason's continued incarceration.
Ellis scrutinized video footage from the party and delved into research on escaping a submerged vehicle, discovering a mere 30-second window for survival. Concerned, she reached out to Brian to review the pathology report, which seemed off to her. Harper mapped out Rain Bradley's route for Ellis, leading them to St Alma Church where they discovered a makeshift bed. Disturbing footage emerged, showing a barefoot Maggie frantically running towards windmills and across a road, only to be struck by a vehicle. A figure emerged from the car to find her unconscious on the pavement. Soon, a forensic team descended upon the church, and Kate notified them of Maggie's discovery.
At the hospital, Linda stood beside Maggie's hospital bed, overwhelmed with emotion. Maggie's wrists bore bruises, and Ellis broke the news that she had been missing for five days. Maggie insisted that Rowan had taken her home, a claim Linda vehemently denied, questioning instead where he had really taken her. Suddenly, the EKG machine beeped, and Maggie's voice fell silent. In the lobby, Rain offered solace to Linda. Ellis informed Kate that Maggie was unaware of Rowan's demise, and Kate revealed the presence of drugs in Maggie's system.
At the accident scene, Ellis revealed to Harper that Rowan and Amy had exchanged texts during the week of Maggie's disappearance and Rowan's death. Bank records showed a transaction of £43 at Felmark Service Station on the preceding Wednesday. Harper's phone buzzed with a call from Belmont, whom he suspected was fishing for incriminating information. Asserting there was nothing to share, Harper dismissed the call.
At the police station, Amy accused Carrie of spiking Maggie's drink with Special K (ketamine) at the pool party, a confession Carrie had allegedly made to Amy three days later. Amy assured them that Rowan would have been enraged had he found out. Later, Ellis confronted Carrie, who denied the accusation and suggested it was Amy who had fabricated the story out of fear that Maggie would come between her and Rowan. Carrie admitted to spiking Maggie's drink impulsively but denied procuring drugs from Carlos, claiming instead that Carlos stored his drugs in The Stonedale Inn's cellar.
Elsewhere, Harper questioned Aaron about Carrie's actions, to which Aaron pled ignorance. Though Rowan had been his best friend, Aaron admitted a preference for Amy over Maggie. He also confessed to disliking Maggie. Kelly stepped in, insisting that Aaron have legal representation for future interrogations.
Belmont steadfastly insists that Carrie must face charges. Ellis counters, arguing that Carrie lacks a vehicle and has no history of violence, let alone the murder of Rowan. Harper interrupts with new information, relaying that Carlos' girlfriend attested to his absence from their home the previous night. Belmont, unwavering, orders them to bring Rain in for questioning. Ellis counters once more, highlighting the absence of any concrete evidence tying Maggie to St Alma's. Yet, Maggie's DNA was indeed discovered on Rowan's hoodie, concealed behind a radiator at the school.
Later, Ellis delves deeper, querying Rain about their encounters at St Alma's. Rain speculates that Aaron could be Rowan's killer. This leads to Aaron being summoned to the police station for interrogation. Under scrutiny, Aaron admits to a sexual relationship with Rain spanning several months, grumbling about Peter's preference for Rowan over him. He fears that revealing his affair with Rain would exacerbate an already tense situation. When confronted with the hoodie found at St Alma's, Aaron claims to have discovered it at the school prior to the official search. Harper chimes in, revealing that Maggie was last seen wearing it before her disappearance. Aaron concedes to taking Maggie to St Alma's, confessing his desire to keep Rowan's hoodie for himself. He emphasizes that Rain is the only one he can confide in without reservation.
Belmont throws another curveball, announcing that the mud on Mason's sneakers matches the mud found on Rowan. Harper notes Mason's presence at the scene of Rowan's death, recounting how Maggie was taken hostage and drugged. She suggests the mud's origin could be anywhere along the Lower Moor, adding that nitrate fertilizer and diesel traces were also found on his clothing. She recalls a report of a farm trespasser, while Mason laments that Linda would eject him if she learned of his return to old habits.
Rowan's car was captured by an ANPR camera on Valentine's Day, heading northwest, with a female passenger visible. Belmont informs Harper of Ellis' abrupt departure from their last case, leaving her team in disarray. In a hospital bed, Maggie recounts Rowan mentioning a task he needed to attend to. His silence and avoidance of the topic puzzled her, and she wonders why he hasn't visited. Linda breaks the news of Rowan's demise to her.
Amidst a phone conversation, Harper is poised to caution Ellis about Belmont's scrutiny of her past when the call abruptly cuts off. Ellis finds her phone's charging cable damaged. The following morning, Harper informs Ellis that Rowan's £43 transaction was made at the Clifftop petrol station, where he also purchased parking on Parr Street. Kate presents her with a photo of the Women's Health Centre, sparking further investigation. At the hospital, Ellis delicately inquiries if Maggie was with Rowan in the car. Maggie firmly denies any intimate relationship with Rowan.
Ellis engages in conversation with Amy, who reveals that her father is absent. Amy's disclosure prompts Ellis to acknowledge her awareness of Amy and Rowan's recent trip to the coast. Ellis confides in Amy, acknowledging the profound difficulty of deciding against motherhood. Curiosity piqued, Ellis inquires about the timing of a particular event, to which Amy responds that it transpired shortly before her mother's demise.
As Ellis prepares to depart, Amy trails after her, urgently pleading for her not to venture inside. Inside, Ellis stumbles upon a makeshift bed and Carlos, lying unconscious on the floor. Amy swiftly slams the door shut, leaving Ellis behind. Meanwhile, Chet is briefed about a potential sighting of Carlos' vehicle heading towards Winnet's Pass, but he dismisses it, intending to retire for the night.
Ellis attempts to contact Chet, only to realize her phone is nearly dead, with a mere 2% battery life remaining. In a desperate bid to communicate, she rummages through Carlos' pockets, but her phone dies before she can send a message. Elsewhere, Amy intercedes on behalf of her father, Eric Mercer, urging him not to repeat his actions.
Eric confronts Ellis, acknowledging her understanding of the close bond between Amy and Rowan. He confesses to barring Amy from seeing Rowan again, claiming Rowan arrived intending harm. Eric portrays Amy as his protector, recounting how she picked up a shovel and struck him three times while Maggie remained oblivious to the commotion. Eric confined Amy to the barn and transported Rowan to the lake, ostensibly to shield Amy. He further admits to intoxicating Carlos with his own supply of drugs.
Ellis suspects Eric of murdering Rowan, contending that Rowan was aware of Eric's years-long abuse towards Amy. She alleges that Eric impregnated Amy and that Rowan clung to life for an additional three hours before Eric allegedly pushed his car into the lake. She warns Eric of a lengthy prison term.
Through Ellis' dying phone, Chet receives a cryptic message bearing the name "Mercer." As Ellis and Eric's altercation escalates into violence, Ellis narrowly escapes and bumps into Chet outside. Belmont seizes the opportunity to claim credit for the arrest, while ACC Leighton informs Ellis that higher authorities are aware of her contributions, hinting at potential future collaborations in emergency situations. However, Ellis expresses dissatisfaction with her involvement's circumstances.
Chet joins the conversation, revealing his contemplation of a career change.
