When Tasha Alexander strolls the streets of Chicago, she doesn't much see Wrigley Field or the Chicago River.

She sees St. Paul's Cathedral and the River Thames and Belgrave Square and hansom cabs. Alexander's imagination is perpetually tuned in to another place and time: London in the late 1800s.

That's the setting for her rollicking, popular series of mysteries featuring Lady Emily Hargreaves, a headstrong woman who smokes cigars, drinks port, reads Homer in the original Greek, slings witticisms with the ease of an Oscar Wilde and solves mysteries with the elan of a Sherlock Holmes.

A Holmes with a lovely decolletage, that is.

Alexander, who lives in Chicago with her husband, novelist Andrew Grant, just published the sixth installment in her Lady Emily series, "A Crimson Warning" (St. Martin's). Previous titles are "And Only to Deceive" (2005), "A Poisoned Season" (2007), "A Fatal Waltz" (2008), "Tears of Pearl" (2009) and "Dangerous to Know" (2010).

The covers all have a lush, dreamy, romantic look that might suggest that they are standard-issue bodice-rippers aswarm with dark, handsome men and cooing damsels in distress — but don't be fooled.

Lady Emily is a pistol.

She's no blushing, flirtatious miss who poses in the corner and bats her eyelashes at the unmarried gentlemen. She's bright, energetic, articulate, stubborn and curious, and when she sinks her teeth into a case — in "A Crimson Warning," the threats involve blackmail and murder among London's most elite citizens — she's relentless.

Moreover, Alexander's heroine has a healthy sexual appetite that she's not shy about satisfying on a regular basis, courtesy of her equally dashing husband, Colin Hargreaves, an agent of Scotland Yard. Her erotic longings — thought by some, then and now, to be absent in all of the prim, proper women of the Victorian era — are just another aspect of Lady Emily's character that sets her apart.

As Emily herself puts it, "I'm fortunate that by accident of birth I'm in a position to pursue my own interests without too much interference."

Translation: When you're rich and well-connected, you can defy convention with impunity. Lady Emily uses her privilege to help others — and to help her husband outwit criminals.

For Lady Emily's creator, the series has been a way to combine her two great passions: reading and traveling. Alexander loves to undertake the copious historical research that undergirds each novel, an effort that has taken her to Britain, France and, most recently, Venice, Italy. She spent several months in Venice last summer, researching the next book in the series, "The Floating City," scheduled to be published in 2012.

"The only sure thing in writing is entertaining yourself," Alexander said in a recent interview. "So if you're not doing that, there's a problem."

The vivacious Alexander is clearly just as smitten with Lady Emily as are her readers. The books sparkle with wit and crackle with action. And the period details — Alexander strives to get everything right, from the hemlines to the food to the architecture to the modes of transport — are fascinating.

"I always wanted to be a writer from the time I was a little girl. But reality got in the way," she said. "I didn't think it was a viable way to earn a living. I was married right after college. Somebody had to get the health insurance! So I took whatever soul-crushing job I could get."

She never forgot her dreams, though. Alexander was born and raised in South Bend, Ind., the daughter of University of Notre Dame philosophy professors Gary and Anastasia Gutting, and she lived as a child in places like London and Amsterdam during her parents' sabbaticals.

"I fell in love with Europe back then," she recalled. As a student at Notre Dame — she graduated in 1992 — Alexander majored in English and medieval studies.

After her divorce from her college sweetheart, she returned to South Bend to be near her family. And she started to write novels — novels set in the exotic locales that had stayed bright in her memory, now supplemented with extensive research.

"I start with diaries and letters. And I read popular literature of the time," Alexander explained. "I still think it's important to go to the places I write about. You can read and look at pictures, but it's hard to know what a place is really like without being there. You have to be immersed."

In 2008, Alexander attended a mystery writers conference in Baltimore. There she met Grant, who, like his brother Lee Child, is a British-born writer of thrillers. After the sort of whirlwind romance Lady Emily would surely approve of, Alexander and Grant were married. They divide their time between their Chicago home and one in Sheffield, England.

"Writing is a job," Alexander said. "You have to sit down every day and just do it. The mechanics are always the same — but every book is different."

Lady Emily would not permit it to be otherwise.

JULIA KELLER, cultural critic for the Chicago Tribune, won the 2005 Pulitzer Prize for feature writing.

jikeller@tribune.com

Twitter @litkell

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