I guess we don't get in.
1 seconds sound clip from Scooby-Doo, Where Are You! - What a Night for a Knight (S1E1).
You can hear this line at 00:07:06.827 in the Blu-ray version of the episode.
Quote context
[...]
- That settles it. There's something fishy going on in that museum.
- Museum?
- Right, Scoob, tonight we're going fishing.
- This place is locked up tighter than a drum.
- Then, like, how do we get in?
- Easy. Shaggy goes through that window up there.
- Why me?
- Because that's a small window, and you're the thinnest.
- Oh, boy.
- Come on, give me a hand with this ladder.
- Well, if we don't get in, we'll never find out what happened to the missing professor.
- Shaggy, you start up, and I'll get the jack out of the Mystery Machine.
- Right.
[...]