True-crime stories are definitely having a moment. With “The People v. O.J. Simpson” sweeping the Emmys and Golden Globes, and audiences transfixed by shows like HBO’s “The Jinx” and the Netflix docu-series “Making a Murderer,” it’s clear that stories depicting actual cases fascinate and enthrall the public. Brad Ricca’s new true-crime/biography, MRS. SHERLOCK HOLMES, is sure to entice such an audience. It reads like the best crime fiction, with breakneck pacing and incredible characters surrounding a heinous and mysterious crime. About one-quarter of the way through the book, I had to put it down to Google “Grace Humiston” because I was incredulous that she was a real person and that this case actually happened. But believe it; it’s all true.

Grace Humiston was born Mary Grace Winterton in New York in 1869. After graduating law school at NYU, she made a living as an attorney helping the most dire cases in the city --- those of the disenfranchised immigrants and working poor through her firm, the People’s Law Firm, in New York City. Her name first came to prominence when she represented a young woman named Antoinette Tolla, who was due to hang for the murder of Joseph Sonta --- a crime the defendant claimed was in self-defense. Grace put her keen investigative skills to work, and with only days before Tolla’s slated execution, she proved Tolla’s claim of self-defense to be factual based on evidence that hadn’t been properly admitted at her trial. Tolla’s execution was commuted and her sentence reduced to 7 1/2 years in prison.

"Ricca’s riveting biography painstakingly joins two literary worlds: a fast-paced, thrilling investigation into a mystifying crime, and a captivating history of a brilliant and compassionate woman far ahead of her time."

Prior to the Ruth Cruger case in 1917, Grace was best known for her investigation into Sunny Side Plantations, a working farm in Mississippi that was luring immigrants with the promise of well-paid work only to exploit their workers with horrible living and working conditions, threats of imprisonment, and back-breaking labor at slave wages. But since the workers usually spoke little or no English and were new to the country, they felt as if they had no recourse. While working for the Justice Department, Grace’s bosses learned of the charges of “peonage” being leveled at the business owners of Sunny Side and sent her to investigate.

Located in Greenville, Mississippi, the plantation was owned by O.B. Crittenden Company, with one of its partners being a very wealthy and well-connected lawyer and Delta political leader. Grace spent nights in the shacks with the immigrant workers and also hired an outside investigator to infiltrate the work site, gaining reams and reams of notes detailing the mistreatment of the workers. Despite political pressure from the company’s powerful alliances --- ties that went all the way up to President Teddy Roosevelt --- and being downplayed as an “hysterical lady” and a “busybody,” Grace’s report finally leaked, and word got out about the inhumane treatment at Sunny Side.

In addition to her tireless fight for the working classes, Grace was becoming known for the figure she cut. Always donning a black dress and being an outspoken divorcee at a time when women didn’t even have the vote made her a formidable woman to be reckoned with. But it was her work on the aforementioned 1917 disappearance of young Ruth Cruger that earned her the moniker of “Mrs. Sherlock Holmes.” After failing to return from picking up her freshly sharpened ice skates, the family of 18-year-old Ruth began to worry. It wasn’t like her to stay out and not contact her family at their Harlem home. Could she have met up with a secret boyfriend? Could she have eloped? Or was something more sinister at play? The police tended to think the former and were dismissive of her father, Henry, and his pleas to find his missing daughter.

After getting little help from the authorities, Henry took his story to the papers and, finally, to Grace. Right away, she began the exhaustive investigation that was not done by police. And most evidence pointed to the motorcycle repair shop of one Mr. Alfredo Cocchi, who ended up fleeing the country fearing that anti-immigrant sentiment might result in him being railroaded in the young girl’s disappearance. Grace brings her trusty friend, Julius Kron, to help her get to the bottom of this nebulous case.

Ricca’s riveting biography painstakingly joins two literary worlds: a fast-paced, thrilling investigation into a mystifying crime, and a captivating history of a brilliant and compassionate woman far ahead of her time. MRS. SHERLOCK HOLMES combines the best aspects of books like THE DEVIL IN THE WHITE CITY with the breakneck pacing and atmosphere of novels like THE ALIENIST and THE GODS OF GOTHAM. Sometimes the stirring action of the missing person case in 1917 might feel thwarted by the chapters detailing Grace’s previous cases, but it’s all necessary information to help inform the character of such a venerable woman of great achievement. It makes for a rewarding read that not only entertains but informs.