You don't how big this thing is.
4 seconds sound clip from the Meet John Doe (1941) movie soundboard.
You can hear this line at 00:58:33 in the DVD version of the movie.
Quote context
[...]
- Incidentally, my name isn't Doe. It's Willoughby.
- Look, John. Something important's happened.
- They're forming John Doe Clubs. We know of 8 and they say...
- To carry out the principles in your radio speech.
- I don't care what they're forming. I'm on my way and I don't like the idea of being stopped either.
- You don't how big this thing is.
- You should see the thousands of telegrams we receive and what they're saying about you.
- It started as a circulation stunt but it isn't anymore.
- Mr. Norton wants to back it, sponsor clubs all over the country.
- He wants to send you on a lecture tour.
[...]