A decent premise adversely affected by how dated some of the attitudes are in the book. First published in 1969, this novel features a persistant sexist slant that was rampant at that time. Tab Hunter (that era's Brad Pitt) is referenced a few times, which is not a problem for older readers, but the book's target audience won't know who they're talking about.
If you want to discuss history, women's rights and changing attitudes about them with your son or daughter, this would be a great book to start with.
I like to read a Lois Duncan story every so often, most of hers are aimed at young adults but they are easy to read without sex, violence, or bad language which makes for a quick easy day's reading which is refreshing sometimes.
They couldn't have just disappeared! Or could they?
That's the way it looks when Dan and Larry don't return from a weekend camping trip in the mountains. Then Joan, Larry's sister, gets a misterious call from a man who says Larry owes him a lot of money. Where could her brother be?