Season 9, Episode 14: "The Strongbox"

You know, it's a funny thing about that bird dying.

I hid the key in Fredo's food dish.

That's a weird coincidence.

-Kramer. -What?

You killed Fredo.

Fredo was weak and stupid. He shouldn't have eaten that key.

Kramer, I need those cufflinks...

...but now they're in the box and the key is in the bird.