Captive Witness — Carolyn Keene

Is absent-minded Professor Bagley a spy on a secret mission? That's what he reveals to Nancy when he desperately needs her help during their student tour of Europe. Their tour leader is also the leader of an important plan to help ten orphaned children escape from behind the Iron Curtain.

But their hostile government will do just about anything--even kidnapping and murder--to keep the ten children from crossing the border. Nancy comes up with a daring plan to help the kids--but it could leave her stranded behind the Iron Curtain in the hands of a very dangerous enemy!