That is where Batman comes in.
5 seconds sound clip from Batman (1966) - A Death Worse Than Fate (S1E10) TV Series.
You can hear this line at 00:13:01 in the Blu-ray version of the movie.
Quote context
[...]
- Well, well. Legal tender after all. Isn't life surprising, hmm?
- You have your money, Eivol. Now, tell me the secret. How do I escape from the Doom-Trap?
- You mean you haven't guessed, Zelda? Even after the hint I gave you?
- True.
- Even I, Eivol Ekdal, with all my twisted Albanian genius. Even I cannot devise the answer.
- That is where Batman comes in.
- Oh, we lure him into the trap? Then he show us the way out?
- Exactly. We use him as our pawn.
- Even if Batman does work out the trick, how can I use it on stage when Batman knows?
- We have an obscure peasant saying in my country: 'Dead men tell no tales'.
[...]