Star Wars Episode 5: The Empire Strikes Back - The Wampa Ice Monster Is Really a Droid!
To do this you must have The Empire Strikes Back, Special Edition!!! In the start of the movie, when Luke is hanging upside down in the cave. Look at the Wampa Ice Monster eating. after Luke frees the light saber, he chops off the arm of the monster. If you look real close, you can see the robot inside.
TESB, it must be the SE