Well, it's beaten me. I'll give 1000 pounds for a practical idea.
6 seconds sound clip from the The Invisible Man (1933) movie soundboard.
You can hear this line at 00:55:00.264 in the Blu-ray version of the movie.
Quote context
[...]
- I understand you have another assistant besides Dr. Kemp. A Dr. Griffin. Where is Dr. Griffin?
- It is Griffin! What's the good of concealing it? It's Griffin, and he's threatened to murder me!
- We've doubled the search party ten miles around Kemp's house.
- Well, it's beaten me. I'll give 1000 pounds for a practical idea.
- He's roaming the country at will. A madman!
- Here I am. Aren't you pleased you've found me?
- Would you like to keep him company?
[...]