Lord Wrath by Sydney Jane Baily

An affable, self-indulgent viscount suddenly finds himself with a singular purpose — to hunt down a vicious murderer. The unassuming, lovely lady who has caught his interest may be his best ally or a shockingly unexpected foe.
When senseless tragedy strikes his family, Lord Burnley takes justice into his own hands. Cutting a swath of vengeance through the heart of London, he nearly takes an innocent life by mistake.
Lady Adelia Smythe is known as a meek and mild wallflower. She has her private reasons for reticence. Yet, when she stands up to the angriest man in England, how could she ever dream her heart would end up yearning for him?
Rage fuels his lordship’s life until he can’t imagine having room for any other emotion. Will he take a chance on a love as strong and fierce as anything he’s ever felt? And when Lady Adelia confesses the truth, will he choose his hatred or his heart?