Collins, M: A Spinster's Guide to Danger and Dukes

"Miss Poppy Delamare has been living a lie. To escape an odious betrothal, she hid as the quiet and unassuming Flora Deaver, secretary to London's most infamous female crime reporter. When her beloved younger sister is accused of murder, however, Poppy returns home to keep her sibling from the hangman's noose. But a collision with the most unexpected--and unwelcome--of travel companions interrupts her journey. To her surprise, the arrogant, albeit handsome, Duke of Langham offers to help clear her sister's name--in exchange for a favor of his own"--