Longshadow (Regency Faerie Tales Series, Book 3)

Proper Regency ladies are not supposed to become magicians - but Miss Abigail Wilder is far from proper. The marriageable young ladies of London are dying mysteriously, and Abigail Wilder intends to discover why. Abigail's father, the Lord Sorcier of England, believes that a dark lord of faerie is involved - but while Abigail is willing to match her magic against Lord Longshadow, neither her father nor high society believe that she is capable of doing so. Thankfully, Abigail is not the only one investigating the terrible events in London. Mercy, a street rat and self-taught magician, insists on joining Abigail to unravel the mystery. But while Mercy's own magic is strange and foreboding, she may well pose an even greater danger to Abigail's heart.