An inquisitive bachelor. A mysterious widow. A dangerous partnership in Regency London.

Idle heir to an earldom, Viscount Northwood has never applied himself to anything important?until a shocking murder shatters the calm of his cozy London square. He has a chance to be useful at last: by solving the crime. The prime suspect is the beautiful but enigmatic widow across the way. Determined to uncover the truth, North calls upon the investigative tricks he's learned from his twin, a former Bow Street Runner.

Hypatia, Lady Cartwright, has spent her widowhood guarding a reputation she can't afford to lose. When her next-door neighbor is found dead, she?not his blood relations?is revealed to be his heir. Fast-gaining a notoriety she doesn't want, the last thing she needs is the square's newest resident: an overly inquisitive and vexingly rakish viscount working to expose her every secret.

Certain she'll be charged with murder, Hypatia agrees to work with the viscount to hunt the killer. Their uneasy alliance may be her only chance to prove her innocence before it's too late.