Dark Rival

Description for DARK RIVAL by Brenda Joyce:

HIGHLAND WARRIORS SWORN TO PROTECT INNOCENCE THROUGHOUT THE AGES...
A golden man, he is called Black Royce--a battle-hardened soldier of the gods. His vows are his life--until he is sent to New York City to protect a Healer from those who would use her powers for themselves. The moment Royce sees beautiful, feisty Allie Monroe, he knows she will be his only weakness--and he is right.

DESTINY IS A DANGEROUS THING
Allie Monroe is more than an heiress. She is a Healer, willing to do anything to save victims of the evil that lurks in the city at night. But alone, she can do only so much--until destiny sends her the darkest Highlander of them all. Then evil strikes and Royce is destroyed before Allie's eyes. Now Allie will do anything to save Royce--even if it means going back in time to a dark, dangerous world. Confronting their enemies could cost not only their lives, but their love--for all eternity.

This is #2 in The Masters Of Time Series.