Augusta is an heiress. As such, she is supposed to make a brilliant match. But she's bored. Bored, bored bored. So she escapes to Bath (with a friend who has had a miscarriage and is in mourning, when does that happen in a romance?) and pretends to be a widow so that she can find a lover to shake up her life.
Joss Everett is one-quarter Indian which sets him outside of society to begin with. Plus, his father was a profligate. He's just trying to help his cousin out with one more problem before Joss can leave his employ. Well, his cousin is actually being blackmailed and Joss needs to sell some of their ancestral lands so his cousin can pay it off. Joss isn't sure how he's going to meet with the movers and shakers of Bath because he's not a part of their society either. But he does know August, especially he knows the fact that she's not a widow. And she knows how to play the middle-class society, specifically how to manipulate the businessmen who think she is nothing more than a fluff-brain.
A good read and one that doesn't seem to connect at all to the previous two in the series (at least, not that I can remember) so it's not necessary to start at the beginning.