You better bring smelling salts back with you.
2 seconds sound clip from the Back to the Future Part II movie soundboard.
You can hear this line at 00:39:38.735 in the Blu-ray version of the movie.
Quote context
[...]
- Wait a minute. We're just gonna leave her here on the porch?
- The disorientation will help convince her that it was all a dream.
- How long do you think she's gonna be out?
- You better bring smelling salts back with you.
- All right. Come on. Let's go, Einie.
- Don't worry. She'll be fine.
- I don't remember bars being on these windows.
- If you need me, I'll be back at my lab dismantling this thing.
- Right.
[...]