Wild about the Witch (Book 6 of Lost Highlander series)

Still trapped in the eighteenth century, Lizzie Burnet is in the clutches of a madman, desperate to escape and reunite with Quinn so she can prove her love to him. Even if it means never getting back to her own time.

Quinn is on his way back to Scotland, hell-bent on finding his sister and pretending Lizzie didn't break his heart.

All the while, Catriona is having the time of her life in the present, as Piper struggles to fight off the evil she thought she'd finally vanquished.
And plan a wedding.

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Be sure to read the entire series in order!
Lost Highlander