Darro by Hazel Hunter

A modern day journalist uncovers a story so bizarre that even she can’t believe it.

When Esme Martinez represents her newspaper for a tour of the famously eerie Scottish castle, she is delighted. Not only is it a great assignment, but also a chance to reconnect with her childhood. But when she ditches the crowd to explore, the castle claims its latest victim.
For Chieftain Darro McKeran, his role as the second in command of the clan comes naturally. As the only full-blooded and younger brother to the laird, he endlessly toils to lessen Tagall’s burden. But when Esme arrives, he begins to long for a life and even a love of his own—to find his unshakeable loyalty beginning to fracture.

But their romantic entanglement couldn’t come at a worse time when their ancient enemy finally breaches the barrier.