Grace Unchained by Heather Walker

After helping Clan McLean drive the vampire scourge from the Isle of Mull, the Cameron brothers return to Ulru with their sweethearts—all but youngest brother Jamie. Jamie flies on to his old Clan home to visit the friends and relatives the brothers left behind. When he arrives, he finds a strange situation waiting for him. Grace Spencer, the last remaining time-traveler from modern America, came through the portal into Jamie’s home village, but she’s not trapped there with no way to get out. To Jamie’s surprise, he learns that Grace can travel back and forth in time and space at will. She can find the portal and cross it whenever she wishes.

Things go from bad to worse in a hurry when Grace brings her husband Mike through to show him what’s going on. She only wants to prove to him she really can move through time, but as soon as they arrive in the village, all hell breaks loose when a pack of giants attack the village and kill Mike. To make matters worse, the McLean brothers appear on the scene. Has Lachlan McLean concocted another insidious plan to betray Clan Cameron after Jamie and his brothers saved their lives?

Can Grace and Jamie find a way to avert disaster before the realm plunges into an era of darkness and destruction?