Author Vicki Berger Erwin remembers when Mexico’s downtown square was bustling. Stores would stay open Friday night and families would gather and then disperse to sample the wide variety on offer.

“You could spend a whole day going from shop to shop,” she said.

That’s how Margaret Mortimer spent one afternoon in 1937. She chatted with friends hanging out in front of Scott’s Store. She picked up a trinket at Pilcher’s Jewelry store, roamed the aisles of Marlowe’s Drug Store and grabbed the most recent edition of a magazine from the racks at Gentle News Agency.

Mortimer was 42 at the time, known as one of Mexico’s “most prominent and charming women.”

Erwin and co-author — also husband — James W. Erwin follow Mortimer’s day in a chapter of a new book from Arcadia Publishing. And with the title “Notorious Missouri: 200 Years of Historic Crimes,” it’s not likely Mortimer’s day is going to end well.

The book details 15 cases. Some, like the murder of Jesse James, are part of the American canon. Others inspired the songs “Stagger Lee” and “Frankie and Johnny.” Mortimer’s tale made headlines in Mexico at the time, but faded from collective memory over the course of time.

“I didn’t know about it,” Vickie Berger Erwin admitted.

Erwin grew up near the fairgrounds and graduated from Mexico High School in 1969. She learned of Mortimer’s fate when someone mentioned it in a Facebook thread.

She began looking into the story.

“Notorious Missouri” came about when an editor approached the Erwins about writing something with a Missouri bicentennial hook. Vickie Berger Erwin has several true crime books to her credit and made the suggestion.

Their research spanned 200 years and all corners of the state to present a sampling of kidnappings, mass murders and other moments of riveting brutality.

Crime dramas carry a particular fascination for many Americans, but Erwin says she does not fully grasp the reason. Perhaps, she adds, there is a need to see justice fulfilled.

“Here I am, a little white-haired grandmother, and I’m one of those people,” she pointed out.

Research on the book was hampered by the pandemic. Erwin and her husband generally travel the state. But often they found hours limited at libraries, archives and local historical societies. They were only able to search the trove at Audrain County Historical Society in person for one day.

In “Notorious Missouri,” readers learn that The Ledger led the way in raising funds to help find the suspect involved in Mortimer’s story. Erwin, who lives in the St. Louis area, writes that $1,000 came in on the first day.

“So much of my life is about growing up in Mexico,” she observed.

A fond memory involved summers at the pool and trips to Dairy Pride with friends.

“For a quarter you could have an ice cream cone and a soda or a kwiki,” Erwin recalled. “Of course, quarters were hard to come by.”

“Notorious Missouri” is available in paperback. It is from Arcadia Publishing and The History Press.