We substitute fake jewels with the real ones. Treat it in a reactor to leave radioactive traces of the thief.
7 seconds sound clip from Batman (1966) - The Penguin Goes Straight (S1E21) sitcom.
You can hear this line at 00:12:16.223 in the Blu-ray version of the TV Series episode.
Quote context
[...]
- Hiring him to guard jewels is like trusting a leaf of lettuce to a rabbit.
- Let's race back and give Ms. Starr a warning.
- Nuisance. She's smitten with him. She'd scoff at us.
- We can't protect her, but we can save her jewels and at the same time set a trap.
- To make copies. I don't know what the real ones look like.
- Correct.
- He has to look at them. That would tip Penguin off.
- Pickup the Bat-phone and call Alfred. Tell him to wait for us in the Bat-cave.
[...]