The Reluctant Widow, by Georgette Heyer
It's long time since I read a Heyer novel; I haven't been in the mood for one for quite a while. I found this on the sale rack at the library, though, and the description grabbed me. I have to say, this is one of the best and most fun Heyer novels I have ever read. It is just great.
Elinor Rochdale, a governess down on her luck, is dropped off by the mail coach and expects to be met by her new employer's servant, so she hops up into the waiting gig that seems to be expecting her. Imagine her surprise when she is taken, not to a spoiled little boy, but to a lord who matter-of-factly asks her to marry his dissolute cousin, who is sure to die soon. Elinor is quickly drawn into a strange situation involving secret staircases, French spies, mischievous young brothers, and all manner of mad goings-on.
Heyer's Regency dialogue is always pretty good, but here I really felt like she surpassed herself with Elinor's wit--and every other character too. It's a wonderful fun and fluffy story. I think I'll see if my 12-yo daughter wants to read it too.