From "Monty Python and the Holy Grail"

GALAHAD: I seek the Grail! I have seen it, here in this castle!
DINGO: No! Oh, no! Bad, bad Zoot!
GALAHAD: What is it?
DINGO: Oh, wicked, bad, naughty Zoot! She has been setting alight to our
beacon, which, I just remembered, is grail-shaped. It's not the first
time we've had this problem.
GALAHAD: It's not the real Grail?