Many heroes of crime fiction are completely unencumbered by personal responsibilities.

Lee Child's Jack Reacher, for instance, seems to roll his odometer back to zero at the start of every novel -- traveling the country without the burden of family or friends.

What sets Michael Sears' financial world investigator Jason Stafford apart from the thriller novel pack are his single dad responsibilities to a young autistic son -- also named Jason, but known primarily as "the kid" -- whose care and challenges are central to the books' narrative development.

The new Sears' novel, "Mortal Bonds," has a humdinger of a crime plot, involving a Madoff-like crook and billions of missing dollars, but the scenes involving Jason's son are just as gripping in their own way.

The author will be talking about the new novel at the Darien Library, 1441 Post Road, Wednesday, Nov. 6.

"For me, this book and all of the books are about Jason's redemption ... discovering himself for the first time," Sears said of what his protagonist is doing with his life after serving jail time for being connected to a Wall Street crime. "I wanted to make him a strong, emotional human being and give him a real challenge on his human side. Raising a child is definitely a challenge, but he has a really challenging child.

"I have always been fascinated by autism," he said, adding his gratitude that neither of his own two sons are dealing with the condition. "I know people who have gone through this and I've done tons of research. There are so many issues in autism that any parent deals with once in a while. Your kid throws a tantrum. (Well) an autistic child might do that eight or 10 times a day."

Sears turned to full-time writing after spending more than 20 years working on Wall Street.

"I got out because I was done. It was my time," the writer said of leaving his previous career. "I had a great run and made a lot of terrific, lifelong friends."

Sears decided to investigate a long-held dream to write, taking a few creative writing courses that eventually led him to the New School in Manhattan and then a private workshop that put him together with professional writers.

"The group is focused on creating publishable work that is commercial, too," he said.

Sears began to explore the crime writing genre because he always loved to read thrillers and mysteries. "I did do research into the other writers who deal with white collar crime and saw that there were not a lot of them, so it became a plan for me."

The writer's studies and research paid off when his first novel, "Black Fridays," was nominated for virtually every crime fiction award last year.

At the recent Bouchercon international crime fiction gathering in Albany, N.Y., Sears won the Shamus Award for best first novel from the Private Eye Writers of America.

"I was floored when I won the Shamus. At the dinner, when I looked around the room, I realized I was in the cool guy crowd," he said of sharing the evening with some of the top writers in the field.

Sears has just sent the third Jason Stafford novel to his publisher and is starting to put together the plot for novel four.

"Not to give a whole lot away, but one of the things I'm thinking about is much in the news these days -- the prosecution of Wall Street individuals and firms," he said, adding that Jason's relationship with "the kid" will continue to be a key element in his stories.

"That's an ongoing process that will always be at the center of the books. And, I have no fear of running out of Wall Street frauds to talk about," Sears said of the future of the series.

"I don't write Sam Spade stories," the author said of including the personal elements that are often cut out of mysteries. "There is a whole lot more going on in life than just solving puzzles."