Must be.
3 seconds sound clip from the Who Framed Roger Rabbit movie soundboard.
You can hear this line at 00:29:22 in the Blu-ray version of the movie.
Quote context
[...]
- I didn't see anything. I came in to work... Come on, Lieutenant...
- Just like a Toon to drop a safe on a guy's head.
- You better wait here, all right?
- Must be.
- Hey, Chisold, get a load of this.
- Didn't you used to be Eddie Valiant?
[...]