Just like that last prank about all those little creatures that multiply when you throw water on them?
7 seconds sound clip from the The Goonies movie soundboard.
You can hear this line at 01:12:21 in the Blu-ray version of the movie.
Quote context
[...]
- Sheriff, look, this time I'm telling you the truth.
- I'm locked inside the Fratellis' basement with this guy.
- Yeah. Like the time 50 Iranian terrorists who took over all the Sizzler steak houses in the city?
- Sloth, get back here. Hold on. Sloth, what are you doing?
- Sloth! Sloth! Sloth's going into the fireplace!
- No, Sloth, it's just your echo.
- Echo!
- No, I'll show you! Don't go down there! It's all dark down there, Sloth.
- It's your echo, Sloth. Echo.
[...]