- Doctor, may I hope that you'll be able to explain to me a happening which, to put it mildly, has always puzzled me. 
- I shall try.
7 seconds sound clip from the Dead of Night (1945) movie soundboard.
You can hear this line at 00:30:58.135 in the Blu-ray version of the movie.
Quote context
[...]
- I am surprised Mr. Craig didn't remember Sally's mother. She seems to me most memorable.
- I'm becoming quite alarmed. By the end of this evening, I shall be just as credulous as any of you.
- Mr. Craig, I can only say the more incredulous the doctor becomes the more I believe you.
- Just a little birthday present.
- Put it on the couch, will you?
- Why don't you open it and see?
[...]

 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)