So presumably the joke is that he’s asking for ketchup in a fancy restaurant. Or something.

But is there some significance to the fact that everybody else has been given large meals while he seems to have just a small sandwich?

(Or a square of tofu, but that’s unlikely)

“That’s the man! I’d know him anywhere.”

If she’s pointing to the guy in the sport jacket, what’s the joke?

If she’s not pointing to the man in the sport jacket, what’s the joke?

Actually, it looks like she’s trying to stick her finger up the police detective’s nose, in which case I might not want to know what the joke is.