Hurry up, Fred. No telling when glowin' gruesome will show up.
4 seconds sound clip from Scooby-Doo, Where Are You! - A Clue for Scooby Doo (S1E2).
You can hear this line at 00:18:17.538 in the Blu-ray version of the episode.
Quote context
[...]
- Scram!
- Man! Lookie there! Like, get a load of those yachts.
- Yeah, and they're being painted over in different colors.
- Hey, look at that yacht. It's the one that vanished in the cove.
- And look! It's tied to a minisub.
- It's just as we suspected, and these clues prove it.
- Then I guess this wraps up our mystery.
- That is, if we can wrap up the ghost.
- Not wrap him up, Shaggy, suds him up.
- Hurry up, Fred. No telling when glowin' gruesome will show up.
- I'm ready with the fire hose.
- I hope your contraption works.
[...]