A Daring Liaison (Harlequin Historical) (Hunter Brothers)

is book #349 in the Harlequin Historical line that is sold exclusively online from Harlequin rather in stores.
==Book Description==
Reunited Under Deadly Circumstances
Tasked with covertly investigating a string of suspicious deaths, Charles Hunter finds himself reunited with Georgiana Huffington, darling of the ton, who broke his heart many years before. She’s a woman with a mysterious past—mere days after taking their vows, Georgiana’s two husbands have perished under dubious circumstances.
As Charles works with Georgiana to prove her innocence, she finds herself captivated by the man he’s become. Still devilishly handsome, he’s now more guarded, more…dangerous. Georgiana fears she’s losing her heart to him, but will her love make Charles the killer’s next victim?
(Description from GailRanstrom.com)