fun fact: None of the actors but Gene Wilder knew that the tunnel scene was coming
like, they had the lines and stuff, but they thought it was just a boat ride. And when the lights came on and he started singing their terror was real
This happened a lot throughout the movie. Which is one of the reasons it’s such a great film. The directors did the same thing when they all saw the inside of the Factory for the first time. They wanted to show the face of pure imagination. To capture it all.