The Nightmare Before (ナイトメア・ビフォー, Naitomea bifō) is the 33rd chapter of Dorohedoro.
We see how Kasukabe, Jonson and 13 are tortured inside a cell in En's mansion, and how the professor boldly refuses to talk about the whereabouts of Kaiman while the cockroach is trying to break his chains and 13 ask whats going on (because his head is a huge mushroom, he have no eyes).
The punishment is over, for now, as the jail keeper spit on their food as he leaves, Kasukabe considers this a new exiting experience and takes notes of everything, Jonson tries to lick Kasukabe's wounds and he ask if Dr. Vaux is ok, the monsters moves his wings and shows the mushroom that once was Vaux safe, also noticing how hard they are on them and how little they would endure this. In the next cell lies Nikaido, locked completely as the contract signed by En starts to melt inside her body so she won't be herself anymore. Kasukame fells that play as a prisoner is over and he tells Nikaido that she does not have to worry about them.
Elsewhere we see Kaiman inside an endless building asking where he is, barely remembering the place as he see his hands covered in fresh blood. He goes trough a corridor, knowing exactly where to go and ends in front a door filled with blood and flies, he feels he don't have to open it, but its already open without him to notice, is a bathroom and the source of flies and blood is a corpse lying on the floor. A phone starts to ring on the corridor, he answers the call shocked to hear nobody when suddenly the corpse from the bathroom, expelling flies appears, and Kaiman wakes up in Tanba's restaurant.
As he realizes that was just a nightmare, he is too shocked to go back to sleep and he goes outside. In Kesber Park he sits in the restaurant's van (parked near) and thinks how scaring is to know about his past. Tanba appeared too and tells him that no matter what, he promises to help him to recover his memories (forcing him in the process to accept his offer), Kaiman ask why he would do that for someone like him, the boss simply replies that's the correct thing to do, and he did the same when he saved Fukuyama even if he had nothing to do with them. The chapter ends with Tanba, after hearing how the lizard head needs to find the Cross-Eyes, tells he knows one.