What's that? Now really? I don't believe you.
7 seconds sound clip from the Secret Shaolin Kung Fu movie soundboard.
You can hear this line at 00:54:56 in the DVD version of the movie.
Quote context
[...]
- Hey little friend, why not let's play for a while.
- Hey, what do you say? You wanna play?
- I don't.
- Why are you always follow me?
- No, not again, I'm sick and tired of it.
- What's that? Now really? I don't believe you.
- Why do you have to kill him?
- For fun.
[...]