38Yrs
“Real cases inspired the stories – fiction let me tell them”
#1
A Mysterious Kill
#2
The Sleeper
Meet the Author
Writing had always been Dan’s quiet ambition.
Originally from Youghal, Co. Cork, Dan is a retired Police Detective with thirty-eight years’ service in An Garda SÃochána. He was involved in the investigation of all categories of crime.
Throughout his professional career, Dan always had a yearning to write a crime novel. On retiring from the Force, he found he was afforded the time and opportunity to realise his ambition.
Dan brings a wealth of knowledge and provides an insight into the way criminal justice systems work both domestically and internationally along with an ability to transport the reader into his story.
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Books will be available to buy / ship from 21st November 2025 in The Book Centre , and Selskar Bookshop, Wexford.
Insight into what inspires Dan
The Story Behind the Stories
For Dan, storytelling isn’t just imagination — it’s memory transformed. After nearly four decades serving on the frontline of Irish policing, he carries with him the voices, faces, and moments that defined a lifetime in An Garda SÃochána. Those years, spent navigating the blurred lines between justice and humanity, left an indelible mark — and a wealth of truths that now find their way into his fiction.
Dan’s professional experiences combined with his imagination, allow him to create authentic, realistic and gripping story lines.
Authenticity from Real Experience
Dan’s novels are steeped in authenticity because they grow from real experience: the quiet courage of colleagues, the unspoken weight of loss, the pulse of an investigation that refuses to rest. Yet, beneath the grit, Dan’s writing reveals a deep compassion for the people behind every case — victims, detectives, and even perpetrators.
Humanity beneath the headlines
What inspires Dan most is not the crime itself, but the resilience of those who face it — the human stories hidden beneath the headlines. Through his work, Dan invites readers into a world he knows intimately, one where justice is never simple, and every mystery carries a heartbeat. Through his writing Dan continues the vocation that shaped him.
Books
A lifetime of experience that now fuels authentic and gripping fiction
A Mysterious kill
Dan O’Sullivan
A Hedge Fund Manager is shot by a sniper in Bryant Park, New York. Detective Jake Tyler and his partner June O’Reilly are tasked to investigate the assassination. They need to connect the dots and fast. Jake has a secret, a previous life in ‘Delta Force’.
The plot takes off with a secret ‘Organisation’ trying to undermine and overthrow the sitting U.S. government. The case leads Jake Tyler on a frantic search to find the killer and try to bring down the ‘Organisation’. Jean Billington, the wife of the Hedge Fund Manager is more involved than first thought.
As the story unfolds a kidnapping of a highly placed politician occurs, a desperate search is launched to find him before the ‘Organisation’ can complete their plan to usurp the government. Can you trust anyone, even those closest to you?
The Defence Intelligence Agency and the FBI work in tandem with Jake Tyler in an desperate attempt to stop the treasonable acts perpetrated by the ‘Organisation’
Jake Tyler has to draw on his Special Forces experience when several attempts are made to neutralise him.
The pace is frantic with many twists and turns along the way with political intrigue and mystery.
If you would like an ‘edge of the seat read’ this should be your novel of choice. The action continues right to the very end. You will not be disappointed.
The Sleeper
Dan O’Sullivan
On a cold, harsh day in New York City, heinous crimes have been committed. The perpetrator is an evil and sadistic psychopath. But apart from his depraved acts against his victims, he hides a much darker secret.
The killer’s secret identity is a mystery to all branches of law enforcement, who are also baffled as to the motive for such crimes
New York City Police Detective, Jake Tyler is given the case. As the investigation proceeds, Tyler discovers that the crimes take a bizarre twist and the hunt for the killer becomes a race against time to prevent an international incident from developing. Tyler is used to playing against the odds as he encounters several political obstacles along the way.
Unknown to Tyler, the killer has top security clearance that enables him to have access to all of law enforcements data bases and computer systems. The killer manages to stay one step ahead of Tyler all the way in a frantic search for the truth, but Tyler is no ordinary Detective and has instincts for sniffing out treachery and subterfuge.
The big challenge for Tyler is can he stop the killer in time. He must solve the mystery before a global security threat goes too far and if not stopped may result in catastrophic consequences.
Once again Jake Tyler will have to draw on his experiences from his Delta Force days. The plot has many twists and turns.
Watch, as the clock ticks down and the free world holds its breath.
What the reader’s are saying
Dont’t take our word for it – here’s what Dan’s reader’s say:
Maria B.
"Excellent thriller…difficult to put down! These books are on par with any on the market currently; all the more special because the author is Wexford based…Fantastic Christmas gifts."
MG
"This was a real page turner. I couldn’t put it down. I loved the short chapters and the intrigue and suspense throughout the book. Brilliantly written. Hopefully there will be many more mysteries for Tyler to solve."
Jack Murphy
"What a book (A Mysterious Kill), I couldn't put it down once I picked it up. The pace is quick, the plot draws you in from the very first page. A real page turner from start to finish. Highly recommended."
Larry Roche
"What a fantastic crime novel, twists and turns from the 1st chapter, just when you think you have the plot sorted ....the story takes you in another direction , so looking forward to reading "the sleeper" and the further adventures of Jake Tyler and June O Reilly"
Kathleen Kinsella
"I absolutely loved both books. Great plots with twists and turns all the way to the end. I was hooked from the start of each book."
Tony Roche
"Excellent thriller .... A non stop roller coaster of twists and turns... I immediately jumped straight into the Sleeper...."
Seamie
"Such a page turner, fastest book I have ever read. Can’t wait for ‘The Sleeper’ to continue on the Jake Tyler journey."
Mags
"The story line is brilliant, lots of twists and turns, with really strong characters. ."
Kevin C
"Excellent storyline & really well written. Looking forward to more."
D. O'Sullivan
"A great book that delivers a gripping, fast-paced thriller which feels powerfully real. The high stakes and political suspense keeps you hooked throughout. A must-read for anyone who loves intelligent, edge-of-the-seat crime fiction"
Jack Murphy
"Just when I thought Jake Tyler couldn't get any better. Once again, the plot explodes with fantastic detail of New York City and the characters involved. Tyler is again on a frantic chase with his partner June O'Reilly to catch the villain . The suspense and intrigue are maintained until the very end. It kept me on the edge of my seat. Looking forward to more adventures for the dynamic Detective Jake Tyler."
Danny
"An excellent book which is gripping and full of suspense. A real page turner."
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