A Gentleman's Honor by Stephanie Laurens

The Season has yet to begin, and the second member of the Bastion Club, tall, handsome Anthony Blake, Viscount Torrington, is already a target for every matchmaking mama in London. None of their flighty daughters can fix his interest, but a certain lady does...

Alicia is living a deception. Desperation has caused the determined but penniless lady to boldly launch her ravishing younger sister into the ton and have her make a spectacular match. By masquerading as the widowed "Mrs. Carrington" Alicia can act as the perfect chaperone…but fashionable ladies are not accused of murder...

When Tony Blake discovers Alicia standing over a dead body in his godmother’s garden, every instinct tells him she is innocent. His connections allow him to take control of the investigation, his social prominence provides her public support, but it is more than honor that compels him to protect her and to do everything in his seductive power to make her his.