Midnight Angel — Julie Beard

Lady Lydia Beaumont may seem like the perfect lady, but she has a secret that could destroy her flawless reputation. She spends her nights disguised as a man, prowling through London's seediest parts to save unfortunate women from the dangers of the streets. But when a fourteen-year-old girl is kidnapped, she has no choice but to turn to the one man who nearly ruined her life...

Lord Hugh Montgomery may be renowned for his investigative powers, but his desperate search for Lydia -- the woman who once tempted him to the edge and beyond -- had been futile. He'd been convinced that she was dead -- yet here she was before him, more beautiful than ever, risking her life by masquerading as the Midnight Angel. Desperate to keep her out of harm's way and win back the trust he'd damaged, he follows her through the city's treacherous streets to find the missing girl. But what will it take to convince Lydia that the passionate love they once shared deserves a second chance?