The Good Place served up another classic twist in its fourth and final season, but the clues were actually in plain view the entire time. Fresh off of last week's tease that a mysterious figure was en-route to the experimental neighborhood, Team Cockroach was trying to resolve a Magic Pictionary crisis when alarm bells started ringing. Rushing to the train station, the ominous newcomer was revealed to be Glenn rather than a version of Michael as had been widely predicted. The put-upon demon came bearing similarly bad news, however: there was still a traitor in their midst.
In a surprising move, Jason figured out that it was Janet rather than Michael who had been replaced. Jason's shrewd deduction came as a result of Bad Janet (who was posing as their Janet) forgetting her "not a girl" disclaimer when labeled as such. While some could question how Jason, of all people, was able to figure it out, it was actually expertly seeded a few episodes ago. Though slow-witted, Jason has often proven himself capable of catching on eventually. In this case, after multiple seasons of needing to be corrected, Jason began using such terms as "not-a-girl-friend" when referring to Janet. As such, it made all the sense in the world for him to notice Bad Janet's slip.
There were a number of other indicators pertaining to the twist. For starters, Janet seemed much angrier of late. Although it was explained away by an exhausting workload, it manifested in a number of telling ways. Most especially, she urged Tahani to punch gossip-columnist John in the face - which, as proven when Shawn's last assigned saboteur, Chris, went on a face-punching rampage through the neighborhood, is distinctly a Bad Place tactic. Similarly, a favored Bad Place torture method is to twist a body until parts snap off. When Janet had to put down Chidi Anagonye's Frankenstein horse creation, they revealed that they'd used a similar, unnecessarily grotesque method - especially given that Michael had revealed previously they could just explode such things out of existence. And speaking of exploding, the lie detector that Janet made conveniently malfunctioned to cause the Bad Place's whistleblower, Glenn, to explode.
Double Agent Janet also led the group to question Eleanor's leadership and spent a lot of time indulging Brent Norwalk, to the point that he was allowed to get obnoxiously drunk during said Magic Pictionary game. Again, at the time, it was portrayed as an inconvenience to Janet. However, with Brent closely resembling Shawn and their beloved demon overlords, it makes all the more sense Faux Janet would subconsciously lean closer to him than anybody else. Even Derek and Mindy's sex-toys provide somewhat of a clue. With everybody (even Michael) apprehensive to touch them, a few of them inexplicably made their way to the living room table during the episode. Given the Bad Place's proclivities, it could only have been Bad Janet that moved them - presumably to have something more in line with their sensibilities than flowers to look at.
Fans may still continue to worry about whether or not Michael is a spy - especially since he is now essentially guiding Jason away from the rest of the group and to the Bad Place. Given the fact Michael's seeming replacement seemed like the perfect red herring to hide the truth of Janet's actual replacement, however, that's probably not the case. Still, given the show's penchant for surprise, fans can never really say never. Whatever the case, there is no denying how brilliantly the show's writers seeded these latest reveals. And everyone will learn soon enough - the truth of Michael and how Jason fares in rescuing the real Janet - when The Bad Place continues.