As the song plays, the cord tightens, and when the song ends, the metal ball is released, rolling along its merry way until...
15 seconds sound clip from the The Great Mouse Detective movie soundboard.
You can hear this line at 00:51:18 in the Blu-ray version of the movie.
Quote context
[...]
- Oh, I love it! I love it! Oh, I love it! I love it!
- I had so many ingenious ideas, I didn't know which to choose. So, I decided to use them all.
- Marvelous, isn't it? But here, let me show you how it works.
- Picture this. First, a sprightly tune I've recorded especially for you.
- Snap! Boom. Twang. Thunk. Splat!
- And, so ends the short, undistinguished career of Basil of Baker Street.
- Yes.
[...]