http://www.youtube.com/watch?v=Fo--9mYFpVM Martian Child is a great movie that deals with attachment theory. It also gives counselors a lot of help understanding how to interact with clients in a productive way.
In this movie the lead actor adopts a strange acting child. He learns how to love and help this child to overcome some major issues that the child had because he was adandoned by his biological parents. The movie shows how the main character who has no idea how to be a parent is able to connect and reach a child who others have tried but have always failed to do.
The reason I choose this movie is because counselors can learn a lot from how the main character was able to love and believe in this child enough to help him overcome major problems. He did not have to use medications or a grand pyschological theory, but through the power of love and seeing the best in the child he was able to change the child in a powerful way.