According to Nielsen Media Research, the episode was seen by an estimated 1.04 million household viewers and gained a 0.5 ratings share among adults aged 18–49.
[1] In its original American broadcast, "Chapter 3" was seen by an estimated 1.04 million household viewers and gained a 0.5 ratings share among adults aged 18–49, according to Nielsen Media Research.
The site's consensus states: "'Chapter 3' successfully synthesizes the stunning visual style and compelling narrative of its predecessors into a solid and entertaining third episode.
"[5] Scott Collura of IGN gave the episode a "great" 8.2 out of 10 and wrote in his verdict, "Legion continues to be stylistically impressive, and its central story involving what's really going on with David remains intriguing.
Club gave the episode an "A-" grade and wrote, "'Chapter 3' is a sharp integration of backstory and adrenaline-laced narrative, creating more intense stakes for our heroes even as they plunge deeper into the morass of David's memories.
"[7] Alan Sepinwall of Uproxx wrote, "When I watched 'Chapter 2', it felt like such a comedown from the premiere that I worried Legion simply couldn't sustain itself.
"[8] Kevin P. Sullivan of Entertainment Weekly wrote, "You know you're talking about an interesting show when the most straightforward episode to date culminates in an Inception-style group dream in which an obese demon creature stalks our heroes.
"[9] Oliver Sava of Vulture gave the episode a 3 star rating out of 5 and wrote, "It's possible that the more accessible storytelling is a reflection of David getting comfortable at Summerland, and it makes me wonder if 'Chapter Three' is intentionally basic to set a point of contrast for strangeness to come.
"[10] Sean T. Collins of The New York Times wrote, "After two scatterbrained episodes... the show now seems ready to get on with the business of making this superhuman a superhero.
"[11] Ron Gilmer of TV Fanatic gave the episode a 4.5 star rating out of 5 and wrote, "The pace slows even more in 'Chapter 3', but the mind bending trippiness doesn't let up one bit.