- Now. First clue was... What room can no one enter?
- A mushroom.

Batman (Adam West), Robin (Burt Ward)

8 seconds sound clip from Batman (1966) - A Riddle a Day Keeps the Riddler Away (S1E11) TV Series.

You can hear this line at 00:11:18 in the Blu-ray version of the movie.

Quote context

[...]

- Once, a long time ago, The Riddler made the mistake of telling me that. It means as long as he dishes out riddles, he's... He's not finished with his plot.

- When the riddles stop, that's when he's ready for his final caper.

- Then he told the truth.

- 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.

- Now. First clue was... What room can no one enter?

- A mushroom.

- Agreed. Uh, the second one. Read it again.

- What is the beginning of eternity, the end of time and space, beginning of every end and the end of every race?

- Golly, Batman. It doesn't seem to make sense.

- Let's see. If your first answer, a mushroom was correct... Why, that's it. Of course.

- You have it?

[...]