Come on, Charlie Brown, wake up.
4 seconds sound clip from the Bon Voyage, Charlie Brown movie soundboard.
You can hear this line at 00:56:49 in the Blu-ray version of the movie.
Quote context
[...]
- I remember Violette often spoke of her grandmother, and an American friend.
- During World War II, many Americans were stationed around here, and in the Chateau Mal Voisin.
- I wish your friends would leave the chateau. They could be in danger.
- Wake up, Charlie Brown. It's your turn to stand watch.
- Wha, wha, what? Stand what? What, what time is it? Who's on first?
- Come on, Charlie Brown, wake up.
- It's very quiet. Nothing has happened.
- Now, remember. I'll be at the cafe for an hour or two.
- You are not to invite those boys in.
[...]

 Dead of Night (1945)
 Dead of Night (1945)  Phantom of the Opera (1943)
 Phantom of the Opera (1943)  Scooby-Doo, Where Are You! (1969)
 Scooby-Doo, Where Are You! (1969)  Halloween III: Season of the Witch (1982)
 Halloween III: Season of the Witch (1982)  Knight Rider (1982)
 Knight Rider (1982)