STARRED REVIEW
April 07, 2015

Derring-do with America’s first woman detective

Behind the Book by

In the summer of 1859, a recently orphaned girl named Nell arrives on the doorstep of Aunt Kitty, whose "pickled onion" face offers her sorrowful niece a less-than-warm welcome. But when Nell discovers her aunt is a detective for Pinkerton’s National Detective Agency, the two end up tracking down thieves and murderers in this fun historical tale. The character of Aunt Kitty is based on real-life Kate Warne, the first female detective in the U.S. Chicago author and former journalist Kate Hannigan shares a bit more behind her new book, The Detective's Assistant.

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In the summer of 1859, a recently orphaned girl named Nell arrives on the doorstep of her Aunt Kitty, whose "pickled onion" face offers her sorrowful niece a less-than-warm welcome. But when Nell discovers her aunt is a detective for Pinkerton’s National Detective Agency, the two end up tracking down thieves and murderers in this fun historical tale.

The character of Aunt Kitty is based on real-life Kate Warne, the first female detective in the United States. Chicago author and former journalist Kate Hannigan shares more about the exciting real-life figure at the heart of her new book, The Detective's Assistant.


Researching and writing The Detective’s Assistant has been a giddy, wind-in-the-hair thrill since the moment I stumbled onto Kate Warne’s name. Really it was just a single sentence about her while researching another story from the same year, 1856, but the moment I read about her I knew I had to learn more. America’s first woman detective? And she had a role in thwarting an assassination plot against Abraham Lincoln?

Her story begins when, as a young widow, she walked into Allan Pinkerton’s National Detective Agency office in downtown Chicago and inquired about a job. Pinkerton wrote that he’d assumed she was there for a secretarial position, but that she gave excellent reasons why he should hire her as a detective.

“True, it was the first experiment of the sort that had ever been tried,” Pinkerton said, “but we live in a progressive age, and in a progressive country.”

He hired her the next day, convinced that she could go, as she said, where no male detectives could by befriending the wives and girlfriends of criminals and crooks and worming out their secrets.

One of the hazards of writing historical fiction is that records don’t always survive. Pinkerton was meticulous about documenting his accounts, his cases and his operatives, but Chicago’s Great Fire in 1871 wiped out much of his writings. So I relied on his detective books, penned later in his career and looking back on the agency’s early adventures.

Pinkerton described Kate Warne as a master of disguise and, along with Timothy Webster, one of the finest operatives he ever employed.

“As a detective, she had no superior,” Pinkerton wrote, “and she was a lady of such refinement, tact, and discretion, that I never hesitated to entrust to her some of my most difficult undertakings.”

Her most important case came in February 1861 after Abraham Lincoln was elected president and had to journey by train from Illinois to the White House. As the Lincoln Special chugged east, the nation was ripping in two. By the time the train was to pass through Baltimore, Pinkerton and his detectives had uncovered a plot to assassinate Lincoln before he could take the oath of office.

Pinkerton’s operatives had swarmed the Baltimore area, and Kate Warne assumed an alias and disguised herself as a Southern belle, befriending the wives and daughters of the Baltimore conspirators. Pinkerton called the information she gleaned “invaluable” and “of great benefit to me” as he made the case for President-Elect Lincoln to slip through Baltimore under cover of darkness rather than in broad daylight, as planned.

When Lincoln finally agreed to the plan, two operatives rode with him on the train, escorting him safely through Baltimore and into the history books: Pinkerton himself and Kate Warne.

This makes for gripping storytelling for history buffs and detective fans, but what about for young readers? I felt like Kate Warne’s story is one young girls should know. Too often it seems that tales of heroism and bravery are limited to one gender. In writing The Detective’s Assistant, I wanted to share the story of a real woman who was brave and bold, full of as much derring-do and confidence as the men of her time.

“Kate Warne felt sure she was going to win,” Pinkerton wrote. “She always felt so, and I never knew her to be beaten.”


Kate Hannigan writes fiction and nonfiction for young readers. She likes to think of writing as a bit like detective work, and she’s a great eavesdropper, though only occasionally is she full of derring-do. Visit her online at KateHannigan.com.

Author photo credit Warling Studios/Picture Day.

Kate Hannigan

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The Detective’s Assistant

The Detective’s Assistant

By Kate Hannigan
Little, Brown
ISBN 9780316403511

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