Reluctant Hostage by Margaret Mayo

"Perhaps I ought to warn you that I make a formidable enemy."

Not that Libby needed warning! It hadn't taken her long to realize that Warwick Hunter wasn't the sort of man who was easily crossed. He believed that Libby's sister had stolen a large sum of money from him. And that was why he seemed determined to turn Libby's dream holiday in Tenerife into a nightmare from which there seemed to be no escape....