Helps to have a story idea

Now that I've settled on a script about a librarian in over his head with a movie starlet, today's lesson on punchlines was a bit easier. I had to come up with several different types of punchlines for part of the story. The ones I worked up are at the bottom.
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Adam is a straight-laced, sheltered librarian who must commit a crime to get a rare and valuable book his university bought.


EXT. BEVERLY HILLS MANSION – NIGHT

ADAM storms down the driveway, his clothes dripping wet and in tatters, the cut by his eye bleeding, again, CASEY hurrying after him.

ADAM
You set me up!

CASEY
I didn’t have any choice! It was the only way I
could think of to get the book back.

ADAM
You mean, get back at your boyfriend by using me to -- !
Wait, wait, wait!

He spins on her, horrified. Water from his hair splashes on her.

CASEY
Watch it!

ADAM
You don’t have it? You don’t have the book?!

CASEY
I…I told you – it’s in a safety deposit box.

ADAM
Oh, God. Oh, no. Don’t tell me Lando’s got it.

CASEY
Okay, it’s his box. When I found out how valuable the
book is, I put it there to keep it safe. But then I caught
him fucking Angelina Castroini and smeared his
Ferrari with dogshit and for some reason that pissed
him off -- .

Adam groans and continues onto the street and down to Beverly Blvd.

ADAM
I don’t believe it. I don’t believe it. How’m I going to explain
this to Vincent? He already thinks I’m a cloistered idiot, but
this was going to show him I could handle the real world.  All
I had to do was fly to LA and pick up a book…and what did
I prove? That I can’t even do that. But you know what’s worse?
An Alice Sixty-five, only the tenth copy known to be in existence,
is in the hands of Neanderthal…no, not even that advanced,
a Tautavel man who probably thinks it’s a fancy form of
toilet paper! If he even knows how to wipe!

CASEY
What’re you so upset about? It’s my book.

ADAM
No, Casey, it was your grandfather’s book! Why he gave it
to you, I have no idea, because you have zero appreciation
for it. You don’t care about anything but you! What’s
going to hurt you; what’s going to help you; and to hell
what hurts or helps other people.

CASEY
Adam!

ADAM
I’m going to lose my job, because of this. Do you get that?
I will lose my job. Does that penetrate any part of your being?
I will be blamed for not getting the Alice Sixty-five for
the University’s collection. Me. Because of this.

He picks at his shirt and then his hair.

ADAM
And this. It’s not something a serious person does. It’s
not something a person who can be trusted does.

CASEY
Adam, you're too young to be one of those.

ADAM

Absurd Request -- Y'know what? Why don't I go home? Then twenty-five years from now, when you've had a chance to grow up, and if you have, why don't you think about that sentence?
Comparison -- Oh God, a woman who can't act her age is telling me how to act mine.
Exaggeration -- No kidding, because apparently I just wet my pants, like a baby!
Insult -- Aren't girls supposed to mature faster than boys, or are you just being contrary to accepted opinion?
Metaphor -- God, George Bernard Shaw once said, Youth is wasted on the young. I finally get what he means.
Misinterpretation -- When're you ever too young to be trusted?
Parody -- How old do I have to be, ninety?!
Rename -- Oh? Well, right now I feel like Methuselah.
Reversal -- And you're too old to act like you're five!
Understatement -- Well, I'm old enough to know that I'm standing in the middle of the street after nearly drowning because a girl I trusted couldn't be.