‘Yes,’ he said, meeting her attempt at stony eyes. ‘Pizazz. You are almost entirely pizazzless, Pip.’

‘I am not pizazzless.’

‘You need to draw people in, intrigue them. Have a word like “kill” or “dead” in there.’

‘But that’s sensationalism.’

‘And that’s exactly what you want, for people to actually listen,’ he said.

‘But all of my options are accurate and –’

‘Boring?’

Pip threw a yellow highlighter at him.

‘You need something that rhymes, or alliteration. Something with . . .’

‘Pizazz?’ she said in her Ravi voice. ‘You think of one then.’

‘Crime Time,’ he said. ‘No, oh Little Kilton . . . maybe Little Kill Town.’

‘Ew, no,’ said Pip.

‘You’re right.’ Ravi got up, started to pace. ‘Your unique selling point is, really, you. A seventeen-year-old who solved a case the police had long considered closed. And what are you?’ he looked at her, squinting his eyes.

‘Lacking, clearly,’ she said with mock irritation.

‘A student,’ Ravi thought aloud. ‘A girl. Project. Oh, how about Project Murder and Me?’

‘Nah.’

‘OK . . .’ He chewed his lip and it made Pip’s stomach tighten. ‘So, something murder, or kill or dead. And you are Pip, who’s a student and a girl who’s good at . . . oh shit,’ he said suddenly, eyes widening. ‘I’ve got it!’

‘What?’ she said.

‘I’ve literally got it,’ he said, far too pleased with himself. ‘What is it?’

‘A Good Girl’s Guide to Murder.’

‘Noooo.’ Pip shook her head. ‘That’s bad, way too try- hard.’

‘What are you talking about? It’s perfect.’

‘Good girl?’ she said, dubiously. ‘I turn eighteen in two weeks; I won’t contribute to my own infantilization.’

‘A Good Girl’s Guide to Murder,’ Ravi said in his deep, movie-trailer voice, pulling Pip up from her chair and spinning her towards him.

‘No,’ she said.

‘Yes,’ he retorted, placing one hand on her waist, his warm fingers dancing up her ribs.

‘Absolutely not.’

If you haven’t yet listened to episode 6 of A Good Girl’s Guide to Murder, look away now. Serious spoilers below.

Of course, many of us knew how this mystery ended, from when it exploded on to the news cycles last November, but the whodunnit wasn’t the whole story here. The real story of A Good Girl’s Guide to Murder has been the journey, from a 17-year-old sleuth’s hunch about a closed case – the murder of teenager Andie Bell, allegedly by her boyfriend Sal Singh – to the spiralling web of dark secrets she uncovers in her small town. The ever-shifting suspects, the lies and the twists.

The final episode certainly isn’t lacking in twists as it brings us the truth, starting with Pip’s shocking revelation that Elliot Ward, her best friend’s father, wrote the threatening notes Pip received during her investigation. Irrefutable proof of his involvement and truly a ‘loss of innocence’ moment for Pip. She and Ravi Singh – Sal’s younger brother and co-detective on this case – believed that Andie Bell might still be alive and Elliot had been keeping her the whole time. Pip confronted Elliot Ward alone and, recounting Ward’s words, the whole story unravels. An illicit relationship between student and teacher, allegedly initiated by Andie. “If true,” Pip theorizes, “I think Andie wanted an escape from Little Kilton, particularly from her father who allegedly, according to a source, was controlling and emotionally abusive. Perhaps Andie believed Mr Ward could get her a place at Oxford, like Sal, so she could get far away from home.”

The night of her disappearance, Andie went to Elliot Ward’s house. An argument ensued. Andie tripped, hitting her head against his desk. But as Ward rushed to get a first aid kit, Andie disappeared into the night. In the following days as Andie was officially declared missing, Elliot Ward panicked, believing Andie must have died from her head injury and when police eventually found her body, there might be evidence that would lead back to him. His only chance was to give them a more convincing suspect. “He cried as he told me,” Pip says, “how he killed Sal Singh.” Ward made it look like suicide and planted evidence so police would think Sal killed his girlfriend and then himself.

But, months later, Ward was shocked to see Andie walking on the side of the road, thin and dishevelled. She hadn’t died after all. Ward couldn’t allow her to return to Little Kilton, and that’s how she ended up his prisoner for five years. However, in a twist truly stranger than fiction: the person in Ward’s loft wasn’t Andie Bell. “She looked so much like her,” Pip claims, “she even told me she was Andie.” But she was actually Isla Jordan, a vulnerable young woman with an intellectual disability. All this time, Elliot had convinced himself – and Isla – that she was Andie Bell.

This left the final question of what happened to the real Andie Bell? Our young detective beat the police to that too. “It was Becca Bell, Andie’s little sister.” Pip worked out that Becca had been sexually assaulted at a house party (nicknamed calamity parties), and that Andie had sold drugs at these parties, including Rohypnol which Becca suspected played a part in her assault. When Andie was out that night with Ward, Becca allegedly found proof in her sister’s room that Max Hastings had bought Rohypnol from Andie and was likely Becca’s attacker (Max will soon face trial for several rape and sexual assault charges). But when Andie returned, she didn’t react in the way Becca hoped; Andie forbade her little sister from going to the police because it would get her in trouble. They started arguing, pushing, until Andie ended up on the floor, unconscious and vomiting. Andie’s post-mortem – completed last November when her body was finally recovered – showed that “Andie’s brain swelling from a head trauma was not fatal. Though it, no doubt, caused Andie’s loss of consciousness and vomiting, Andie Bell died from asphyxiation, choking on her own vomit.” Becca froze, allegedly watching Andie die, too shocked, too angry to save her sister’s life. Hiding her body because she was scared no one would believe it was an accident.

And there it is, our ending. “No angles or filters, just the sad truth of how Andie Bell died, how Sal was murdered and set up as her killer and everyone believed it.” In Pip’s scathing conclusion, she picks out everyone she finds at fault for the deaths of these two teenagers, naming and blaming: Elliot Ward, Max Hastings, Jason Bell (Andie’s father), Becca Bell, Howard Bowers (Andie’s drug dealer), and Andie Bell herself.

A Good Girl’s Guide to Murder stormed to the top of the iTunes chart with its first episode six weeks ago and it looks set to stay there for some time. With the final episode released last night, listeners are already clamouring for a season two of the hit podcast. But in a statement posted to her website, Pip said: “I’m afraid my detective days are over and there will not be a second season of AGGGTM. This case almost consumed me; I could only see that once I was out the other side. It became an unhealthy obsession, putting me and those around me in considerable danger. But I will finish this story, recording updates on the trials and verdicts of all those involved. I promise I will be here until the very last word.”