The 10th Kingdom2000

Frog:
One door leads to safety. One door leads to a horrible death. [Croaks] You may ask me one question. Ribbit. But I always lie.

Wolf:
Oh, I learned this in school but I could NEVER remember it!

Virginia:
If we ask him which one's the safe door...

Wolf:
Well then he'll lie, and say it's the other one. Or is it the other way around?

Virginia:
I don't know!

Tony:
All right, all right. Wait, wait! I have a question! What is the point in having a door that has a horrible death behind it? Huh? [picks up frog]

Frog:
Get your hands off me!

Tony:
What does that achieve?!

[Tony starts walking towards the doors, holding the frog]

Frog:
What are you doing?

Tony:
I mean, what is the purpose of your life? Just to be a pain?!

Frog:
Don't touch me there, only my girlfriend touches me there!

[Tony throws the frog through one of the doors]

Frog:
WHOA!

[Tony slams the door; it shakes violently as a large explosion occurs behind it]

Wolf:
I guess it's the other one.