It's important to remember that not every use of the definite article signifies foreknowledge, or even uniqueness. For example, I can say:
The lion is the king of the jungle.
or:
The band's percussion section will practice on the drums in the morning.
without any prior mentions of wild animals, jungles, or drum sets, and the sentences still sound grammatical, idiomatic, and well-formed.
I often encourage learners to sift through the various uses of the definite article found in a good dictionary to see how the word the has many uses. Macmillan contains this gem of a definition, which could explain a lot of instances that might puzzle a learner:
the - used when you are referring to familiar things that people deal with regularly :
I looked up at the ceiling. Suddenly all the lights went out.
Incidentally, there are times when either the or a could be used, with little shift in meaning or nuance. I believe you've found one of them in Chris Rock's routine:
"Little does he know he's just taking the bait for the big bust"
"Little does he know he's just taking the bait for a big bust"
Either sentence means, "Little does he know he's about to get arrested."
I think it sounds just a smidgeon funnier with the, because, worded that way, the situation seems like more like an inevitability; however, I think you'd be hard-pressed to find a dictionary definition that says:
the - used when describing something seemingly inevitable : the big traffic jam at the end of the day
I think that's a legitimate usage, though. The OED includes this definition, and it's not far off:
the - Before a noun, used to indicate a particular instance that is most relevant in this context :
Are you going down to the house?