Undercover Duke by Sabrina Jeffries

Sabrina Jeffries, one of the best-known names in historical romance, weaves an enchanting Regency romance with a mystery at its core, as half-siblings investigate the truth about their mother’s succession of beloved husbands – and their own surprising identities as eligible young nobles.

Along with his half-siblings, Sheridan Wolfe, Duke of Armitage, is determined to solve the mysteries behind the suspicious deaths of their mother’s three husbands. His investigations bring him into dangerous proximity with the captivating Vanessa Pryde, but the duke, still haunted by a tragically lost love, is resolved to resist the attraction. Besides, lovely Miss Pryde seems utterly smitten with a roguish London playwright…
Vanessa’s theatrical flirtation is intended only to break through the duke’s business-like demeanour and guarded emotions, for it is Sheridan she truly has her sights, and her heart, set on. As the duke’s jealousy becomes evident, the two find themselves propelled into a scheme involving a pretend engagement, a secret inquiry – and a perhaps not-so-secret leap into true love…