Jeepers! Someone's going into that old mansion.
3 seconds sound clip from Scooby-Doo, Where Are You! - What the Hex Going On (S1E6).
You can hear this line at 00:02:14.701 in the Blu-ray version of the episode.
Quote context
[...]
- Well, we're almost to the Wetherby Estate, gang.
- It sure is nice of Sharon to ask us up here for the weekend.
- There's so many groovy things to do.
- Yeah, like swimming and eating and tennis and eating and riding and eating... and eating and... Huh?
- Jeepers! Someone's going into that old mansion.
- Like, wow. Who'd do a kooky thing like that?
- Well, the last few nights, we've been hearing a lot of strange noises.
- And now it looks like my Uncle Stuart has vanished.
[...]