What?
3 seconds sound clip from Batman (1966) - A Riddle a Day Keeps the Riddler Away (S1E11) TV Series.
You can hear this line at 00:10:33 in the Blu-ray version of the movie.
Quote context
[...]
- Riddle me this, crime fighter. What room can no one enter?
- If you figure it out, look for another royal riddle in this crown.
- That ends any chance of tracking him with the homing device. Shall we after him in the manhole?
- We'll never find him. There're hundreds of tunnels down here.
- A riddle a day keeps The Riddler away.
- What?
- When the riddles stop, that's when he's ready for his final caper.
- That diamond tiara wasn't what he was really after.
- Right, Robin. But we have two more riddles to tell us what it may be.
[...]