13:26 Jun 13, 2011 

Who is the man, and what happens after that? Is the man in a position to expose the demon's sins/crimes to the public, to the police, etc.? Although I am stretching a bit now, perhaps he means "I'm going to expose you."

Definition of expose in this context:
Make known to the public information that was previously known only to a few people or that was meant to be kept a secret

If the word Dateline is truly in reference to the television program, then the reason it is capitalized is because it refers to the show and titles are always capitalized. Again, though, I might be stretching things a bit. It is just a guess based on what you have described.

11:06 Jun 13, 2011 

I searched again. Actually it's called a "devil's trap"

11:00 Jun 13, 2011 

Yes. He was entrapped! it's a thrilling talking about demons. What happens is that a man drew some sign on the ground where the demon stands so the latter can't move. Can we say that "I'm gonna Date line you" is Im gonna "entrap you"?? Also why is it capitalized?

09:42 Jun 13, 2011 

Whatever the case is, though, I doubt very much that it has anything to do with the International Date Line.

09:41 Jun 13, 2011 

Actually, if you read more about the program, you will see that one of the tactics used by journalists on this show is to entrap people like child predators and other criminals to expose their crimes to the public. Perhaps the phrase you mentioned could thus mean to entrap someone in the same manner. Again, hard to say without knowing more about the context.

09:38 Jun 13, 2011 

The first thing that came to mind is the popular news program Dateline:

http://en.wikipedia.org/wiki/Dateline_NBC

Maybe it means putting someone (like a politician) through hard questioning on this program. Hard to say without knowing more about the context.

00:23 Jun 13, 2011 

Can we translate "I'm gonna Date Line you" as سأحد من حركتك بخط تاريخ ?? coz the verb is capitalized. That's why I thought it's related to the Int'l Date Line.
Thanks.