It took three decades, and as many attempts, but author Wayne Johnston has finally published a work of fiction that's based on a family secret.

The Mystery of Right and Wrong is a story inspired by trauma his wife went through, growing up with a father who sexually abused his four daughters.

"It occurred to me that for a writer not to write about this, even though knowing so much about it, would be almost exactly tantamount to sweeping it under the rug exactly the way that society does with sexual assault," Johnston told Matt Galloway on The Current.

The book tells the story of a man who falls in love with a woman who is the youngest of four daughters. Her Dutch-born father, Hans, lived in Amsterdam during the Second World War, and says he was in the Dutch resistance. It comes to light that the four were sexually assaulted by their father.

Johnston knew even a fictional version of the story would reveal a big secret about his wife and her family, so in an a show of solidarity, he reveals his own secret it the book.

In the afterword, he explains he struggles with obsessive compulsive disorder.

"I felt like an act of something like that was needed to demonstrate my integrity as a writer and my sincerity as a person in writing about these things," said Johnston.

Wayne Johnston didn't know his wife had been abused until one day when a man came to his door in tears. Johnston had never met the man, but he claimed to be his brother-in-law, just recently married to his wife's sister. The two sisters were not in touch, so Johnston didn't even know he had a brother in-law.

The brother-in-law told Johnston that his wife had had a breakdown, was in the hospital, and that she had revealed she'd been chronically sexually assaulted by her father as a child.

"He said, 'do you understand what I'm saying?' And I said, 'yeah, I'm very sorry to hear it, but I do understand what you're saying,'" said Johnston.

"He said, 'I don't think you do.' He said, 'what is the chance that a man who has four daughters and no sons would only sexually assault one of his daughters and leave the other three alone?' And then it hit me, then my world was completely knocked out of its axis."

Johnston said his life became divided into two parts — before the visit, and after the visit. And he knew from that moment one day he would write a book related to this tragedy.

While the father was never formerly reported, Johnston said he and his wife did confront the man, but he never admitted to anything. Both his wife's parents are now dead.

The book created a great internal struggle for Johnston, he said, as he found himself asking if he should write the book at all — and if so, how?

Johnston finished the first version of the book while living in St. John's, N.L., but after it was done, he decided it wasn't right. He felt it came across as too vindictive, and didn't work, so he destroyed it.

"I went out into the streets of St. John's, holding this book in front of me as if it was a bomb that needed to be defused. I walked down the street and people saw me, I don't know what they thought. I tossed the book into a dumpster," said Johnston.

On his second attempt, while living in Toronto, he decided that version wasn't right either, and once again found a dumpster for his work.

"I thought that if it was around the house, if it was in the house, I would definitely go back and try to perfect it, and I knew it was imperfectible," said Johnston.

On his third attempt, 30 years after that stranger came to the door, Johnston finished The Mystery of Right and Wrong. Separating the real people from the characters finally freed him to write the story, he said.

"I was finally able to find a structure and a voice and some literary devices that allowed me to get into the minds of the characters, and be inspired by the real events, but spend less effort at actually trying to imagine what really happened, and instead create a work of art inspired by what had happened," said Johnston.

Now that the book is out, Johnston feels a sense of relief. He'd been working on the book, off and on, for 30 years.

"I feel that that great piano weight is off my back simply because the book is something that I've been trying to write for so long, and at least I don't have to keep on trying to write it," said Johnston.