I opened the gate to their pen, but they wouldn't run.
4 seconds sound clip from the The Silence of the Lambs movie soundboard.
You can hear this line at 01:11:26 in the Blu-ray version of the movie.
Quote context
[...]
- They were slaughtering the spring lambs?
- No. First I tried to free them. I...
- I opened the gate to their pen, but they wouldn't run.
- They just stood there, confused. They wouldn't run.
- But you could, and you did, didn't you?
- Yes. (4)
- I took one lamb and I ran away as fast as I could.
[...]