The subtitle gives perhaps a better indication of the contents than the main title. There are twenty-eight brief biographies, about six pages on average, ranging from "Saint Matthew, Extortionist" to "Venerable Matt Talbot, Chronic Alcoholic." In his introduction, Craughwell explains the theme behind the selection:
At least since the nineteenth century many authors have gone out of their way to sanitize the lives of the saints, often glossing over the more embarrassing cases with the phrase "he/she was once a great sinner." I don't doubt the hagiographers' good intentions, but I can't help thinking it is misguided to edit out the wayward years of a saint's life...
The point of reading these stories is not to experience some tabloid thrill, but to understand how grace works in the world. Every day, all day long, God pours out his grace upon us, urging us, coaxing us, to turn away from everything that is base and cheap and unsatisfying, and turn toward the only thing that is eternal, perfect, and true -- that is, himself...
[The message of] great sinners who became great saints... is reassuring: if these people can be saved, then so can you!
And in fact, Craughwell records the facts (and the legends) in an admirably forthright, non-tabloid style. Bad behavior is understood broadly, ranging from "St. Vladimir, Fratricide, Rapist, and Practitioner of Human Sacrifice" to "St. Peter Claver, Dithering Novice," and in a couple of cases, the misbehavior may be entirely legendary.
The full list of saints:
St. Matthew, Extortionist
St. Dismas, Thief
St. Callixtus, Embezzler
St. Hippolytus, Antipope
St. Christopher, Servant of the Devil
St. Pelagia, Promiscuous Actress
St. Genesius, Scoffer
St. Moses the Ethiopian, Cutthroat and Gang Leader
St. Fabiola, Bigamist
St. Augustine, Heretic and Playboy
St. Alipius, Obsessed with Blood Sports
St. Patrick, Worshipper of False Gods
St. Mary of Egypt, Seductress
St. Columba, Warmonger
St. Olga, Mass Murderer
St. Vladimir, Fratricide, Rapist, and Practitioner of Human Sacrifice
St. Olaf, Viking
St. Thomas Becket, Hedonist
St. Francis of Assisi, Wastrel
Bl. Giles of Portugal, Satanist
St. Margaret of Cortona, Rich Man's Mistress
Bl. Angela of Foligno, Gossip and Hedonist
St. Ignatius of Loyola, Egotist
St. John of God, Gambler and Drunkard
St. Camillus de Lellis, Cardsharp and Con Man
St. Philip Howard, Cynic and Negligent Husband
St. Peter Claver, Dithering Novice
Ven. Matt Talbot, Chronic Alcoholic
As you can see, it's a varied list. Some of their stories are well-known, some relatively obscure.
I should point out that Craughwell leaves implicit what he calls the message of these stories, that no one is beyond salvation. There's very little editorializing, systematizing, or moralizing. Perhaps the closest he comes to this is in writing, "It is safe to say that under the formal process of canonization that has been in place in the Catholic Church for the last several hundred years, Olaf would never have made the cut."
Limiting Saints Behaving Badly to biography makes it a hard book to fault. It does raise some interesting questions -- not least what we today should say and think of St. Olaf -- without trying to answer them, but that leaves the reader free to come up with his own answers. And his own questions, too, for that matter.
I'd think this book could lead to some good discussions for a book club, and I intend to suggest it to my parish's DRE as a possible resource for teenage catechesis. (A few misbehaviors don't make suitable reading for younger children.)
There's a five page bibliography, so although you could get the gist of most of these lives at e.g. Saints O' the Day, most of the sketches are more extensive and detailed than you're likely to find online.