Sister Agatha: The World’s Oldest Serial Killer by Domhnall O’Donoghue

Sister Agatha is 118 years of age, whose vim and vigour would put the most robust athletes to shame. However, during a routine check-up, her doctor claims that she has just a week to live – inconvenient, seeing as the beloved sister once made an improbable vow: to be the oldest person in the world. At last count, she was the fifth.

Never one to admit defeat, Sister Agatha concocts a bold Plan B. Using her final days, she intends on travelling the world to meet the only four people whose birthday cakes boast more candles than hers.

And then, one by one, she will kill them.


My review

Being exactly half Sister Agatha’s age, I’m particularly full of respect for and envy of this elderly lady’s amazing good health, irrepressible feistiness and single-minded ambition. She has no shortage of personality, and has led a very fulfilling life, despite most of it being spent in a religious institution. But in this quirky story, she finally comes into her own when, with the credit card she’s ‘borrowed’ from the convent, she sets out to bump off the four old biddies who are standing between her and her goal. She hasn’t thought things through very hard, content to rely on her wits, which are as sharp as they’ve ever been, but with some fortuitous coincidences and several huge dollops of luck, she rapidly gets underway.

‘Sister Agatha: the World’s Oldest Serial Killer’ is a hoot, with a lively plotline, a cast of eccentric characters (including two particularly horrendous mothers), settings all over the world and tongue-in-cheek comedy that’s decidedly dark in places.

It’s totally original and a joyous riot of a book!


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Author bio

Hailing from Navan in the royal county of Meath, Domhnall is a graduate of the Bachelor in Acting Studies Programme, Trinity College Dublin, later completing a Master’s in Screenwriting at Dún Laoghaire IADT.

He now works as an actor and a journalist, dividing his time between Galway, where he films TG4’s award-winning series, Ros na Rún, Dublin and Venice, where he and his Italian lover continuously promise their well-worn livers that they will refrain from quaffing so much Prosecco. (Unfortunately, it seems some vows, just like nearby Rome, were not built in a day.)

Wine-drinking aside, for more than four years, Domhnall has also enjoyed the responsibility of being Assistant Editor at Irish Tatler Man, a title whose various awards includes Consumer Magazine of the Year. Thanks to this role, he interviewed a host of high-profile names such as Tommy Hilfiger, Chris Pine, Kevin Spacey, David Gandy, and Jacques Villeneuve.

Domhnall has written for the majority of Ireland’s leading newspapers and magazines, including the Irish Independent, The Irish Times and RTE. He also writes a monthly column in Woman’s Way, the country’s biggest-selling weekly magazine.

His first novel, Sister Agatha: the World’s Oldest Serial Killer, was released in 2016 to critical acclaim (Tirgearr Publishing). His second and third books, Colin and the Concubine and Crazy for You were published by Mercier Press, Ireland’s oldest publishing house.


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