Before I start, I must be clear that I actually LIKE many romance novels. I have read all kinds, and I have been a fan of Victoria Holt's for some time. Sadly, The Captive is not the best of Victoria Holt's work. As I said, I usually enjoy her books--the heroines are generally more along the lines of "Jane Eyre" than "Weeping Victim" in that they often are bold, intelligent women who have to find their ways in the world alone, and can't necessarily rely on their looks or charms. Some of the heroines in her books have unconventional occupations (art restorer, for example) despite the Victorian era settings, and most don't go into their situations looking for love. However, they always find love, and generally find a fairly interesting mystery as well. This book showed a lot of promise at first, but then let me down.
Rosetta Cranleigh comes from a family of academics--parents so wound up in their research they barely realize she exists. She grows up relying on the family's servants and a young governess. Then one day her parents decide that she might in fact not be a waste of their time, and decide to take her with them to the Middle East on a research trip. During the voyage, Rosetta meets some boys, and then is shipwrecked with those very same boys (what a coincidence!). The three of them are rescued by corsairs, who sell Rosetta to a harem. The book sort of sells itself as being mostly about her escape from the harem, but as it turns out, that's only about 25 pages in the first third of the book, and then there's a whole laborious murder mystery after that.
Frankly, the book seemed like three different stories (early family life / harem / murder mystery) uncomfortably shoehorned together. I will admit that despite the downfalls, I did greatly enjoy many of the characters in the book, and found them amusing and somewhat interesting.
I would probably not recommend this book, but instead one of Holt's other works like Mistress of Mellyn or The King of the Castle.