Showing Captive Witness by Carolyn Keene

On a student tour through Europe, Nancy discovers that their leader is on a secret mission to transfer ten refugee children from an iron curtain country to freedom! Before the mission is completed, Nancy receives an urgent message from her father concerning a missing entry in a foreign film festival. Undaunted and clever, Nancy pursues an intriguing clue found in a student’s wheelchair and finds herself in great danger.