The episode kicks off with the police arriving at the residence of Carwyn Rees (played by Kristian Arthur), only to discover his lifeless body bearing a gunshot wound to the head. At first glance, and by all appearances, it seems like a case of suicide. As Janie Mallowan (Gwyneth Keyworth) interrogates the neighbors, she unexpectedly bumps into John Chapel (Timothy Spall), a retired TV detective. Recognizing him instantly, her heart skips a beat, but to her surprise, he slams the door shut in her face, feigning ignorance of her identity.
However, the tables turn when she flashes her badge and reveals her police affiliation. After a brief exchange, John inquisitively asks if she's there to grill him about Carwyn's demise. She assures him that it was a suicide, but he steadfastly counters that Carwyn was undoubtedly murdered. Puzzled, she inquires about the basis for his conviction. He cites Carwyn's heartwarming habit of crafting pop-up cards for his cleaner's son every Christmas. Knowing Carwyn's cleaner visits on Mondays, and being the considerate soul he was, John finds it inconceivable that he would take his own life on the very day she was due to arrive. Despite John's insistence, Mallowan remains unconvinced, arguing that people can sometimes behave out of character. He retorts by stating that one's actions are always consistent with their inherent character, using her and her car as an analogy. This comment riles her up, prompting her to storm out in frustration.
Later on, Mallowan approaches DCI Barry Clarke (Steffan Rhodri), enquiring about the possibility of becoming a Detective Inspector. Clarke offers words of encouragement, suggesting she'd make a fantastic DI one day, but gently reminds her that she's only been a Detective Sergeant for a mere five minutes. Their conversation is abruptly cut short when Mallowan receives a call from Helen Baxter (Alexandria Riley), who informs her that Carwyn's death was, in fact, not a suicide.
Mallowan conveys the tragic news of Carwyn's demise to Danielle Rees, portrayed by Amy Griffiths, and inquiries whether the deceased had any adversaries. In response, Danielle reveals that Carwyn and his business associate, Ceri Richardson (played by Oliver Ryan), had stirred up a hornet's nest among environmental activists with their latest development project.
Having concluded her conversation with Danielle, Mallowan makes a detour to John's place, where she presents him with a mug. She guesses the reason behind his relocation, drawing attention to a photograph adorned with a bridge in the backdrop. Curious, she inquiries whether he and his wife once vacationed here. He clarifies that it was actually their first abode together but prefers not to dwell on the past. As they engage in casual conversation, Mallowan is poised to solicit his assistance in the case, but John anticipates her request, already aware of her intentions. He suggests they tackle the investigation from the café and promptly exits.
At the café, John shares with Mallowan an intriguing observation: Carwyn's sudden shift from a morning bacon sandwich to a bowl of muesli, a change he's attributed to a possible affair, prompting Mallowan to joke about him watching the film 'Babe' for inspiration. John further notes that Carwyn had also embarked on a running routine. This discussion sparks a revelation in John – Joyce Pugh (played by Marilyn Cutts), the nosy neighbor across the street, who usually keeps tabs on everything, mysteriously stayed away during the police presence yesterday. Suspecting she might know something, Mallowan conducts a quick search on her phone and discovers that Joyce recently made headlines for her inability to maintain order at a council meeting.
Mallowan then seeks the perspective of Alys Evans (portrayed by Bettrys Jones), who was expelled from the same council meeting after threatening Carwyn. Alys admits to being emotional but emphasizes that the trees in question date back to the 9th century. As for her whereabouts during Carwyn's murder, she asserts she was on a school trip. Alys also reveals that Carwyn deceived many people.
Before heading to converse with Joyce about organizing a fundraising effort for Danielle, John finds himself engrossed in a peculiar discussion about the case with his feline companion, Alan. Joyce, still firmly convinced that the case points to suicide, reveals she can't recall the last time she conversed with the deceased. Ava (played by Eryn Kelleher) interjects abruptly, disclosing that they had actually spoken to Carwyn just the previous week. Following a brief exchange of pleasantries, John skillfully draws her out, revealing that Carwyn's youthful personal assistant had been making significantly more frequent visits of late.
DCI Evan Chaudhry (portrayed by Rithvik Andugula) reaches out to Mallowan, sharing gossip that Carwyn had quite the reputation as a ladies' man. Moreover, he had been siphoning funds from his business, Rees New Homes, directly into his personal savings. Intrigued, Mallowan devises a plan to interrogate Ceri.
During their confrontation, Ceri maintains his alibi, claiming to have been at the show home site on the morning of Carwyn's demise. Mallowan probes further, inquiring whether he was aware of Carwyn's alleged embezzlement from the company. He admits to harboring suspicions, which led him to conduct some sleuthing of his own, ultimately uncovering the truth.
John ventures to inspect one of the houses within Carwyn's development, where he uncovers intriguing snippets about the late developer's character. He learns that Carwyn was not only an exceptional leader but also someone who relished getting involved in the nitty-gritty. Intriguingly, there was a contentious altercation between Carwyn and one of the electricians. As John surveys the premises, he notices an inconsistency in the paint job of one room, which seems distinctly out of place.
Meanwhile, at the precinct, Mallowan is engrossed in discussing the case with Barry and Evan. Her concentration is momentarily broken by a text from John, informing her that he is in the reception area. He presents her with a photograph of the flawed paintwork, emphasizing that Carwyn, a noted neatness freak, would never have overlooked such a detail. Additionally, John shares his conversation with Joyce. Just as Mallowan prepares to respond, Barry enters the room, making his stance clear: he opposes Mallowan collaborating with John on the case. This prompts a heated exchange between Mallowan and John. Their spat is abruptly halted by Evan, who announces that he has discovered something significant from the CCTV footage.
Mallowan brings in Alys to quiz her about her whereabouts and presents her with photos taken at Carwyn's residence. Alys concedes to taking a drive to gather her thoughts but categorically denies any involvement in Carwyn's demise. Mallowan observes that whenever Carwyn's name is mentioned, Alys deflects the conversation, hinting at unresolved feelings. Alys eventually admits to having an affair with Carwyn but steadfastly refuses to take responsibility for his murder.
Seeing the need to reconcile, Mallowan apologizes to John and solicits his assistance. He concurs, emphasizing the importance of focusing on the elements that deviated from Carwyn's usual behavior. The most glaring anomaly, they agree, is the tape affixed to the wall. Just as they settle down for tea to delve deeper into the case, John experiences an epiphany.
Mallowan and John ventured to an auction hosted by Rees New Homes, their mission to confront Joyce. John elucidated that Carwyn had overlooked the red and green tape adorning the wall due to his colorblindness, a condition he shared with Ava. Joyce conceded that Carwyn had discovered Ava was his flesh and blood, sparking his desire for a relationship with her. Yet, despite these revelations, Mallowan and John insisted that Joyce was not Carwyn's killer, albeit she had instigated a sequence of events. The revelation that Carwyn intended to bequeath his business to his daughter did not sit well with Ceri. Complicating matters further, Ceri and Danielle were engaged in an illicit affair, rendering Danielle's silence upon encountering Ceri at their residence all the more suspect. Ceri and Danielle steadfastly denied any wrongdoing until Mallowan unveiled her evidence: Danielle had crafted a watertight alibi by orchestrating a notebook delivery, as captured by CCTV footage. Moreover, the murder weapons traced back to Ceri were undeniably linked to the crime.
Back at the precinct, Ceri and Danielle finally confessed, yet Barry remained disgruntled due to John's involvement in the case. Mallowan conceded that John had lent her a helping hand, but emphasized that it was Barry's mentorship that had ultimately guided her to the solution. He commended her efforts but warned against collaborating with John again.
Later, Mallowan and John reconvened to celebrate their triumph, only for her to seek his assistance in another case. And so, the episode concluded on this cliffhanger.
