Seventeen years ago, a character began talking to me. His name was Warren Hoyt and, in whispers, he described his horrifying fantasies, which would inspire his brutal crimes in Boston. Such a clever killer had to be matched with an equally clever detective, and that’s how Detective Jane Rizzoli was born. When she first walked on to the pages of The Surgeon, I didn’t even realize that Jane was a heroine. Det. Thomas Moore was the protagonist in that story, and Jane was merely his annoying partner, a plain and scruffy woman with a huge chip on her shoulder. I saw no reason to make her likeable because I was going to kill her by the end of the book.

But her death didn’t quite go as planned. In the course of writing The Surgeon, I began to admire Jane for her drive and intelligence, qualities that her male colleagues didn’t always appreciate. I also learned about the obstacles she faced in her life and her career. She’d grown up with two brothers who taunted her, and continually had to prove herself in a male-dominated profession. She was very much an outsider, a position that I could identify with. When I reached the scene where Jane was lying wounded and helpless and about to die, I couldn’t kill her. Not only did she survive the book, she was the one who cracked the case.

After finishing The Surgeon, I planned to write a medical thriller, but the character of Jane Rizzoli never left me. I kept wondering: what is Jane doing now? Has she finally earned the respect of her colleagues? I put aside my medical thriller and instead wrote The Apprentice, this time with Jane front and centre as the heroine. I also introduced a new secondary character, a medical examiner named Maura Isles. Maura was everything that Jane was not: reserved, logical, and cautious. She was also mysterious, a woman who wouldn’t reveal her secrets even to me. By the time I finished writing The Apprentice, I was so curious about Maura that I then had to write a book about her. In The Sinner, we meet Maura’s ex-husband, who returns to wreak havoc in her life. We also meet Father Daniel Brophy, the man who will bring Maura both joy and heartache in the years to come.

Without planning it, I now had a three-book series starring Rizzoli and Isles. Every book I’ve written in this series has been driven by my curiosity about these two women and what’s happening in their lives. In the course of twelve books, Jane has gotten married and had a child. Maura has fallen in love and suffered for it. In the early books, Jane and Maura are merely colleagues who respect each other, but soon their friendship deepens. They’ve had their ups and downs, of course; every friendship does, and there’ve been periods when they’re scarcely speaking to each other. But whenever a case turns dangerous, they always stand side by side because they trust each other completely.

Sixteen years later, I now think of Jane and Maura as friends. Sometimes they’re difficult or they drive me crazy. Sometimes they do the unexpected, just as real people do. They’re certainly not perfect, but they are fiercely loyal and ethical women who always try to do the right thing. What more could you ask of a hero?

How many of Tess Gerritsen’s Rizzoli and Isles novels have you read? Let us know in the comments below – and check out all the books in the series here.

Tess Gerritsen Bestselling author Tess Gerritsen is also a physician, and she brings to her novels her first-hand knowledge of emergency and autopsy rooms. Her thrillers starring homicide detective Jane Rizzoli and medical examiner Maura Isles inspired the hit TV series Rizzoli & Isles. But Tess’s interests span far more than medicine and crime. As an anthropology student at Stanford University, she catalogued centuries-old human remains, and she continues to travel the world, driven by her fascination with ancient cultures and bizarre natural phenomena. Follow Tess on Twitter.

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