In this, Lines of Enquiry’s inaugural ‘Case Notes’, John Sweetman introduces a new strand of his hit true crime podcast series. Stepping away from any one specific case in detail and instead revisiting past investigations and responding to listener questions, John takes us behind the scenes of Lines of Enquiry.

This first episode of ‘Case Notes' is also the last in Season 1 of Lines of Enquiry. Reflecting on his first season, John is in conversation with Darren Cleary, creator of Lines of Enquiry and Head of Digital Audio at Bauer Media, who hears all about Season 2, which goes out on January 6th, 2026, with further 'Case Notes' also on the way.

Remember, you can contact the show at [email protected] 

When Anne O'Sullivan was diagnosed with terminal cancer, tensions within her family about who would inherit her substantial plot of farm land came to the surface.

Soon, Anne would find herself awake before dawn, running through fields and ditches to a neighbour's house to get help as a terrible darkness descended on the family farm.

This is a tragic story that saw a family torn apart as their home became consumed by fear and threats of violence towards Anne and her eldest son, Mark. Those rising tensions would lead to the most unfathomable and shocking moment of hatred and rage.

In this episode of Lines of Enquiry, John tracks the descent into violence and revisits his case notes on the letters that proved crucial to any understanding of events of that tragic day.

Presented by John Sweetman

Created by Darren Cleary

Episode Written by Eoin Brennan

Script Edited by John Sweetman

Research by Siobhan Maguire & Eoin Brennan

Executive Produced by Eoin Brennan

Executive Produced by Ruth Fitzsimons

Produced by Siobhan Walsh

Produced by Siobhan Maguire

Sound Design and Editing by Neil Kavanagh

Audio Editing Support by Ed Smith

Marketing Support by Bríd Walsh and Róisín Reilly

Social Support by Mark Hayes and Robyn Ree

Artwork and Graphics by Eric Rowntree

On St Patrick’s weekend 2024, 23-year-old Kelly Lynch travelled from her home in Armagh to Monaghan to support her boyfriend after a sudden death in his family. Two nights later, on the walk home from the pub in the town, on the Friday night of a busy bank holiday, Kelly disappeared.

She was found in the Ulster Canal on the Sunday morning. Gardaí said Kelly had drowned and quickly confirmed they were not treating her death as suspicious. But as the details emerged, her family were left with devastating questions.

In this episode of Lines of Enquiry, John Sweetman follows Kelly’s final movements, the contradictions at the heart of the investigation, and the campaign led by a family desperate for answers.

Presented by John Sweetman

Created by Darren Cleary

Episode Written by Darren Cleary

Script Edited by Eoin Brennan

Produced by Siobhan Walsh

Produced by Siobhan Maguire

Executive Produced by Eoin Brennan

Executive Produced by Ruth Fitzsimons

Sound Design and Editing by Neil Kavanagh

Audio Editing Support by Ed Smith

Marketing Support by Bríd Walsh and Róisín Reilly

Social Support by Mark Hayes and Robyn Ree

Artwork and Graphics by Eric Rowntree

The prime suspect walks free for the murder of Nora Sheehan after the death of the pathologist left the DPP's case unable to proceed to trial. 

In this second chapter of a two-part investigation, John Sweetman looks at how four decades after Nora Sheehan’s disappearance and death in 1981, advances in forensic technology breathed new life into a long-dormant investigation. 

 In this episode, we explore how preserved evidence from fibres and paint fragments to a partial DNA profile was re-examined by investigators as as long-preserved traces ignite a renewed hunt for answers.

Presented by John Sweetman
Created by Darren Cleary
Episode Written by Darren Cleary
Script Edited by Eoin Brennan
Executive Produced by Eoin Brennan
Executive Produced by Ruth Fitzsimons
Produced by Siobhan Walsh
Produced by Siobhan Maguire
Sound Design and Editing by Neil Kavanagh
Audio Editing Support by Ed Smith
Marketing Support by Bríd Walsh and Róisín Reilly
Social Support by Mark Hayes and Robyn Ree
Artwork and Graphics by Eric Rowntree

In June 1981, Nora Sheehan left the South Infirmary Hospital in Cork and disappeared into the night. In the hours that followed, she was seen by witnesses walking alone after midnight, a familiar figure on dark roads and quiet streets.

Days later, her battered body was discovered dumped in woodland far from the city. Her murder shocked Cork and marked the beginning of a case that would stretch across generations.

In this opening chapter of a two-part investigation, John Sweetman reconstructs Nora’s final movements, the witness sightings after midnight, and the immediate aftermath of her disappearance. What emerges is the story of a vulnerable woman who vanished in plain sight and a killing that would become one of Ireland’s longest-running cold cases.

Presented by John Sweetman

Created by Darren Cleary

Episode Written by Darren Cleary

Script Edited by Eoin Brennan

Executive Produced by Eoin Brennan

Executive Produced by Ruth Fitzsimons

Produced by Siobhan Walsh

Produced by Siobhan Maguire

Sound Design and Editing by Neil Kavanagh

Audio Editing Support by Ed Smith

Marketing Support by Bríd Walsh and Róisín Reilly

Social Support by Mark Hayes and Robyn Ree

Artwork and Graphics by Eric Rowntree

The Walsh house in rural Connemara is quiet by 4am on the 22nd of June 1985. Earlier in the night it was full of people celebrating the brief return of two family members who had emigrated. But now the friends, neighbours and even the local Gardaí who had attended the party have all dispersed. So, when 14 year old Jacquie Walsh wakes up in the middle of the night the only person she sees is her mother, 33 year old Barbara asleep on the couch. Jacquie tries to wake her but when she does not stir, Jacquie places a pillow beneath her head and drapes a blanket around her before heading to bed. Barbara Walsh was never seen again.

For years, her family were told that the young mother of 7 must have wandered off – Despite not having a car and living over 50 miles away from Galway city.

In this episode, former Garda forensic detective John Sweetman goes back to 1985 and examines the original investigation, the new leads for the cold case team and asks where is Barbara Walsh?

 Presented by John Sweetman

Created by Darren Cleary

Episode Written by Siobhan Walsh

Script Edited by Eoin Brennan

Executive Produced by Eoin Brennan

Executive Produced by Ruth Fitzsimons

Produced by Siobhan Walsh

Assistant Produced by Siobhan Maguire

Sound Design and Editing by Neil Kavanagh

Audio Editing support by Ed Smith

Marketing support by Bríd Walsh and Roisin Reilly

Social support by Mark Hayes and Robyn Ree

Artwork and graphics by Eric Rowntree

Gardaí are called to a house in north Dublin, where they make a grim discovery. 72-year-old Marie Dillon has been found murdered in a violent attack inside her home.

As investigations begin, it becomes clear there are no suspects and no obvious clues.

In this episode of Lines of Enquiry, John Sweetman revisits the case that brought him face to face with his first murder scene at just 26 years of age, in his early days training to become a forensic fingerprint expert.

Presented by John Sweetman 

Created by Darren Cleary 

Episode Written by John Sweetman

Script Edited by Eoin Brennan 

Executive Produced by Eoin Brennan 

Executive Produced by Ruth Fitzsimons 

Produced by Siobhan Walsh and Siobhan Maguire 

Sound Design and Editing by Neil Kavanagh 

Audio Editing support by Ed Smith 

Marketing support by Bríd Walsh and Roisin Reilly 

Social support by Mark Hayes and Robyn Ree 

Artwork and graphics by Eric Rowntree

Video by Ger Walsh

On 4 January 2005, 11-year-old Robert Holohan left his home to play on his bike in Midleton, Co Cork and never returned. What began as a desperate search for a missing boy quickly became one of the most emotionally charged murder investigations Ireland had ever witnessed. Thousands turned out to look for him. Gardaí deployed every resource available. For a week, the country hoped against hope. Then came the devastating discovery: Robert had been killed. The search for the young boy soon became a hunt for a killer. The eventual truth would prove to be more devastating than anyone had imagined.

Presented by John Sweetman

Created by Darren Cleary

Episode Written by Darren Cleary and John Sweetman

Script Edited by Eoin Brennan

Executive Produced by Eoin Brennan

Executive Produced by Ruth Fitzsimons

Produced by Siobhan Walsh

Assistant Produced by Siobhan Maguire

Sound Design and Editing by Neil Kavanagh

Audio Editing support by Ed Smith

Marketing support by Bríd Walsh and Roisin Reilly

Social support by Mark Hayes and Robyn Ree

Artwork and graphics by Eric Rowntree

A sinister, disturbing handwritten letter arrives into Garda HQ. It has been sent anonymously to a school in the midlands. There are 23 pages, promising terrible crimes to come, and detailing the writer’s twisted plans to abduct and kill teenage girls.

Soon after, two more arrive – again sent to schools across the Irish midlands. Gardai then realise this is not their first encounter with the anonymous writer, as they discover records of a strange hideout found in the woods in Offaly many years ago. More letters arrive, sent to Garda stations and found by members of the public.

Fear spreads as the writer goes further and begins naming potential targets, all teenage girls at a local Offaly school. Gardai now face a race against time to find him, before he can put his evil plans into action.

As part of our launch week of Lines of Enquiry we are releasing two episodes this week, including this one. From next week we will release weekly, every Tuesday morning.

Presented by John Sweetman

Created by Darren Cleary

Episode Written by Eoin Brennan, Siobhan Maguire and John Sweetman

Executive Produced by Eoin Brennan

Executive Produced by Ruth Fitzsimons

Produced by Siobhan Walsh

Assistant Produced by Siobhan Maguire

Sound Design and Editing by Neil Kavanagh

Episode Edited by Eoin Brennan

Editing support by Ed Smith

Marketing support by Bríd Walsh and Roisin Reilly

Social support by Mark Hayes and Robyn Ree

Artwork and graphics by Eric Rowntree

When 27-year-old Mary Gough was found dead in her home in Balbriggan in 2001, it looked like a tragic accident. Gardaí were called to what appeared to be a fall down the stairs.

But as investigators examined the scene, small details began to raise doubts, marks that didn’t fit, timelines that didn’t match, and a story that started to change.

In this episode, former Garda forensic detective John Sweetman revisits the case, piece by piece, to uncover how investigators learned that what looked like a household accident was, in fact, something far more sinister.

Presented by John Sweetman

Created by Darren Cleary

Executive Produced by Eoin Brennan

Executive Produced by Ruth Fitzsimons

Produced by Siobhan Walsh

Assistant Produced by Siobhan Maguire

Sound Design and Editing by Neil Kavanagh

Editing support by Ed Smith

Marketing support by Bríd Walsh and Roisin Reilly

Social support by Mark Hayes and Robyn Ree

Episode Written by Darren Cleary

Episode Edited by Eoin Brennan

Artwork and graphics by Eric Rowntree