According to Nielsen Media Research, the episode was seen by an estimated 0.434 million household viewers and gained a 0.2 ratings share among adults aged 18–49.
In March 2018, it was reported that the fourth episode of the season would be titled "Chapter 12", and was to be directed by Ellen Kuras and written by series creator Noah Hawley and co-executive producer Nathaniel Halpern.
[1] In its original American broadcast, "Chapter 12" was seen by an estimated 0.434 million household viewers and gained a 0.2 ratings share among adults aged 18–49, according to Nielsen Media Research.
Club gave the episode an "A-" grade and wrote, "The Groundhog Day shenanigans ultimately come across like a scolding lecture staged for our benefit, not for David's.
"[5] Alan Sepinwall of Uproxx wrote, "But where I can often just accept Legion's stylistic flourishes as something superficially impressive that doesn't withstand closer scrutiny, 'Chapter 12' put in the real work of placing us inside Syd's head, experiencing her life the way she has, feeling the same hurt and alienation she's suffered.
"[6] Evan Lewis of Entertainment Weekly wrote, "As a deep character dive on Syd, who often tends to feel aloof and underdeveloped, this episode is a welcome change of pace, and it brings the scale of the stakes from global catastrophe to personal development in a way the season has desperately needed.
"[8] Nick Harley of Den of Geek gave the episode a 4 star rating out of 5 and wrote, "For the first time this season, it feels like David and Syd are back on the same wavelength.
The episode ends with Lenny showing up at Division 3, perplexingly in the flesh, but after the dazzling, emotional 43-minute journey we've been on through Syd's memories, the cliffhanger doesn't hit as hard as it maybe should.
The show has made the rest of Division 3 seem like villains at times and reluctant allies at others, but is David now working against the greater good?