[[quoteright:350:https://static.tvtropes.org/pmwiki/pub/images/friend_tower.jpg]]
* The flashback to the origins of the Friend cult.
* "[[http://manga.animea.net/20th-century-boys-chapter-30-page-17.html We're friends, right?"]]
* Kenji's first meeting with Friend on-stage; it goes from the surreal as Friend descends from the rafters seemingly under his own power, to the chilling as Friend asks how Kanna is, then revealing they're ''her father''.
* While also listed as a SugarWiki/{{Funny Moment|s}}, the chapter 'Robot Conference' where the engineer is trying to explain the mecha problems. All these full-grown adults are coming up with ideas for a giant robot ''designed to kill thousands of people at the very least'' like little boys playing a game.
** Made even more chilling when the engineer insists he's leaving and is promptly told ''he'll never see his daughter again''; looking around the room, he's met with a number of smug smiles.
* The events that transpired in [[spoiler:the science room]] also qualify, both in story and out.
* The entirety of Koizumi's stay at "Friend Land" tapped directly into a person's small, natural measure of paranoia very effectively. The "Bonus Level" arc was especially creepy.
** [[MadnessMantra Help me help me help me help me...]] [[GoMadFromTheRevelation I met Friend and played with him.]]
* The few moments where Urasawa drew mysterious characters in a stylized ghostly art-style. Specifically [[spoiler:Professor Shikishima's daughter in 21st Century Boys when she was shown in her creepy nurse outfit with those cold dead eyes.]]
* Koizumi being forced to stay at [[spoiler: Sadakiyo's]] house while he puts on his best [[Film/{{Psycho}} Norman Bates]] impression.
* The reveal that there were [[spoiler:three boys]] wearing masks.
* [[UnPerson "I told everyone you were dead."]]
* The lab incident. [[spoiler:Fukubei in hanging from the ceiling with a rope around his neck, ecstatic beacuse he made the others witness a miracle... and then begins to choke]]. No wonder poor Donkey jumped out of the window.
* Majoume has a disturbing encounter with Friend in the virtual reality game, and exits to see Friend, disconnected from the game, standing over him. Not only is this freaky as hell, [[spoiler:it's a major hint that there is more than one Friend.]]
* The end of the virtual reality game, when [[spoiler:Friend takes off his mask and you see old Sadakiyo's head attached to a kid's body]]. And just everything about Tomodachi Land, really.
* [[spoiler: Fukubei looks in the mirror. He has no face]].
* That freaking tower with the eye symbol. There's something utterly disturbing about that.