A mad scientist kidnaps and mutilates a trio of tourists in order to reassemble them into a human centipede, created by stitching their mouths to each others' rectums.

Katsuro: Oh shit! I have to shit!
Dr.Heiter: Swallow it, bitch!
Dr.Heiter: I'll explain this spectacular operation only once. We start with cutting the ligamentum patella, the ligaments of the kneecaps, so knee extension is no longer possible. Pulling from "B" and "C" the central incisors, lateral incisors and canines from the upper and lower jaws, the lips from "B" and "C," and the anus of "A" and "B," are cut circular along the border between skin and mucosa, the mucus cutaneous zone. Two pedicelated grafts are prepared and lifted from the underlying tissue. The shaped incisions below the chins of "B" and "C" up to their cheeks connecting the circular mucosa and skin parts of anus and mouth, from "A" to "B," and "B" to "C," connecting the pedicelated grafts to the chin-cheek incisions from "A" to "B," and "B" to "C," creating a Siamese triplet, connected via the gastric system. Ingestion by A, passing through B, to the excretion of C. The human centipede, first sequence.
Dr.Heiter: I don't like human beings.
Dr.Heiter: Feed her! Feed her!
Dr.Heiter: Do you already regret your little escape? In fact, I'm thankful for it, because now... I know definitely you are the middle piece!
Katsuro: [upon discovering he is in the clutches of an evil doctor] The Japanese possess unbelievable strength when backed into a corner!
Lindsay: We just got a little lost, okay?
Jenny: A little lost? We're not a little lost.
Lindsay: ...Yes, we are...
Jenny: We're *really* lost!
Dr.Heiter: They'll arrive in half an hour... maximum.
Dr.Heiter: I'm Dr Josef Heiter, retired, but still very well known as the leading surgeon in separating Siamese twins. Six months ago, I designed a never seen operation, not separating any more but creating. I transformed my three Rottweilers into a beautiful three hound construction. Good news, your tissues match. So, I'll explain this spectacular operation only once.
Katsuro: God. Are you God? I'm just a puny insect. I cast out my parents, left my child, dismissed their love and led a selfish life. Just like an insect. No, my existence is even lower than insects, but... but dear God... that's how I've lived, and this is my punishment. I want to believe that I'm still a human being... Hey girls! Hey mister! What an insane world we live in.
Dr.Heiter: Now you can bite me. Bite my boots! Bite my boots!
Dr.Heiter: How dare you to turn your back on me!
[first lines]
Jenny: [speaking on a hotel phone] Hi. Yes, um, I was wondering if I could get driving directions to a nightclub called Bunker. Yes, Bunker. How exactly would I get there?
[last lines]
Det. Kranz: Voller! Voller!
Jenny: [from trailer]
[Jenny is trying to follow the road map to the nightclub in the car]
Jenny: I think we're supposed to turn.
Lindsay: I thought you knew exactly where we were going!
Jenny: [the car breaks down in the middle of the road and the girls are stuck. They look shocked and scared] What... was that?