Verbal Kint: The greatest trick the Devil ever pulled was convincing the world he didn't exist.
Verbal Kint: Keaton always said, "I don't believe in God, but I'm afraid of him." Well, I believe in God, and the only thing that scares me... Is Keyser Soze.
Verbal Kint: How do you shoot the Devil in the back? What if you miss?
Cop: I can put you in Queens on the night of the hijacking.
Hockney: Really? I live in Queens. Did you put that together yourself, Einstein?
Verbal Kint: You think you can catch Keyser Soze? You think a guy like that comes this close to getting caught, and sticks his head out? If he comes up for anything it'll be to get rid of me. After that... My guess is you'll never hear from him again.
Verbal Kint: Back when I was picking beans in Guatemala, we used to make fresh coffee. Right off the trees, I mean. That was good. This is shit, but hey, I'm in a police station.
Verbal Kint: People say I talk too much.
Hockney: Yeah, I was just about to tell you to shut up.
McManus: GIVE ME THE FUCKING KEYS, YOU FUCKING COCK SUCKER MOTHER FUCKER!
Dave Kujan: I'll tell you what I know. Stop me when this sounds familiar. There was no dope on that boat.
Police Interrogator: You know what happens if you do another turn in the joint?
Hockney: Fuck your father in the shower and then have a snack? Are you going to charge me dickhead?
Answer: Soze ended up back under arrest and for some questioning as 'Verbal Kint'. He never really vanished, he's just playing two parts/people. He really vanishes off the scene by the end of the movie after he tricks Kujan.
With the exception of what's known to have happened on the dock, the entire story is a lie told by Verbal Kint to Agent Kujon. Kujon realises this after Kint leaves the office but not in time to catch up. The entire movie is about a habitual liar making up a story about what happened on the dock. He may be Keyser Soze or an alter-ego variant but even Keysers rep is subject to question as it was told by the same liar. Verbal himself said about Keaton, "He was a grounded guy, a cop. If you think the husband did it then you're right." He was telling on himself as sociopaths will do when they think they're smarter than everyone around them.