"The Untamed Mackenzie" by Jennifer Ashley

This is book 5.5 in the Highland Pleasures series, which I again read out of order because I didn't know it existed (like my previous post, it is a novella as opposed to a full novel).  This one is about the Mackenzie brothers' half-brother, Detective Inspector Lloyd Fellows.  The old Duke of Kilmorgan is his biological father, but because his mother is an English barmaid, he was never acknowledge by the horrible old man.  However, his brothers have welcomed him into the family, and he finds that he's closest in looks and temperament to the current Duke, Hart Mackenzie.  Fellows works for Scotland Yard in London and is well known for his ability to successfully capture every criminal he goes after, but when it comes to matters of love he turns his back.  He's fallen for the sister-in-law of Mac Mackenzie, a woman far above him in station and manners.   Lady Louisa Scranton has had her eyes on Fellows since the Duke's wedding the previous year where she discretely initiated a scorching kiss with him, but she's been accused of murdering a wealthy bishop and her future looks bleak.  Can Fellows stay impartial while he leads the investigation or will he and Louisa's mutual attraction jeopardize his career and her life?  Another great Mackenzie story from Ashley; I just wish it had been longer and we were able to get the know the heroine and hero as well as we did the other couples in the series.  194 pages (Kindle edition).