Tony Muggivan is a farmer. One wet night in February 1989, Brendan O'Donnell entered his life and that of his family. He had absconded from Trinity Detention Centre in Dublin and had been missing for a week. He turned up at Tony Muggivan's door, dirty, dishevelled and starving. The Muggivans took him in. Tony had never seen O'Donnell before.

The next day, Tony Muggivan, in agreement with the Gardai, got a week's grace for O'Donnell and began a search for help. It was clear that he should be in a psychiatric unit, not a detention centre. Doctors, social workers and the Gardai all agreed that this was the best course of action. As there was no place for him in Co. Clare, Muggivan took O'Donnell to hospitals in Ballinasloe and Galway, where they refused to admit him. Frustrated and angry, Muggivan and O'Donnell returned home. Over the next five years Brendan began living rough and embarked on a campaign of armed robbery and mayhem in the east Clare area. It was evident he was out of control.

In 1994 O'Donnell murdered Imelda Riney, her three-year old son Liam and Fr. Joe Walsh. It was one of the most shocking crimes of modern times. O'Donnell was convicted in 1996 and died in prison in 1997 in circumstances that have never been fully explained by the authorities.

Tony and J.J. Muggivan recount Brendan O'Donnell's tragic life, and highlight the failures of the system to help a deeply disturbed boy who later became a pyschotic killer. Tony Muggivan had known that something awful was going to happen: for five years, he had tried and failed to get the Irish social and medical system to offer appropriate treatment to a desperately sick young man.

A Tragedy Waiting to Happen reveals the truth behind the headlines and the real Brendan O'Donnell.