After the family and their friends have fun at an Escape Room, Stewie builds a machine that will allow him to remain smart forever after Brian claims that being dumb is a Griffin heritage, but it instead transforms him into what he should have always been — an actual baby.
Tropes:
- A Day in the Limelight: The final few minutes is a Pixar-esque short starring Cleveland.
- Baby Talk: Stewie talks like after he gets turned into an actual baby.
- Body Horror: Some of Stewie's transformations invoke this.
- Bus Crash: To keep up the trend of spiting Cleveland’s cancelled spin-off, his mom, Cookie Brown, is revealed to have died in a passing joke, similar to how Donna’s mother Dee Dee died in a passing joke in “Candy Quahog Marshmallow”.
- Disproportionate Retribution: The whole plot happen because Brian lied to Stewie and made him feel that he was going to lose his intelligence, all because Stewie called him out for taking credit for his ideas.
- Extreme Omnivore: Brian played a video of Chris with a Rubix cube as a baby backwards to make it look like he was solving it rather than what he was actually doing with it. Eating it.
- Face Death with Dignity: After everything he's been through, the Brian from our timeline ambivalently goes through with the new timeline's Brian drowning him.
- Green-Eyed Monster: Implied to be part of the reason Brian tricked Stewie, as he was jealous of Stewie being much smarter than him.
- Ignored Expert: Meg effortlessly manages to get the answer to the first clue but the family ignores her. While they erronously continue to try and answer it themselves, she just hands them the key without them even noticing.
- Jerkass: Brian. He, out of pettiness, tricked Stewie into thinking he was going to lose his intelligence when he gets older and his first reaction to learning that Stewie has been turned into a real baby was to take smug satisfaction in finally being smarter than him. And he only tries to change him back, not out of guilt, but because he got tired with having to take care of, in his own words, "a screaming bag of leaking crap".
- Jerkass Has a Point: During dinner, the family gets upset when Brian calls them "Basic Bitches", but Meg admits that it is "kinda true".
- Lampshade Hanging: Stewie admits Cleveland got a short because the overall episode ran short.
- Properly Paranoid: When Stewie sees Brian time travel into his room, he asks in an annoyed tone, "Oh no, what did you do?"
- Shout-Out: The final part of the episode with the short of Cleveland and the mailboxes is meant to reference Pixar shorts. Stewie also references the Pixar short Bao.
- One of the mailboxes is marked "Carlos & Elle", a reference to the characters Carl and Ellie from Up.
- During his transformations in his machines, Stewie turns into Pikachu, Audrey II, and finally a Gremlin-esque monster when the machine breaks.
- During the Escape Room scene, the Brown family sinks into the couch, which is from a scene in the Jordan Peele horror film Get Out (2017). Cleveland even lampshades the title. Also, Stewie figures out an escape room riddle as being a reference to Fibonacci numbers in Dan Brown's The Da Vinci Code, and he tells Brian. Then Brian of course pretends he figured it out on his own.
- Unwitting Instigator of Doom: Brian ended up being a catalyst for the episode's conflict by pranking Stewie by lying about his supposed upcoming hereditary stupidity.
- What the Hell, Hero?: Brian gets called out several times in this episode.
- Stewie rightly calls him out for copying his answer to the escape room and taking credit for it.
- After Stewie becomes a real baby, Brian tries talking to Chris and makes fun of the family and Chris calls him out on this.
- Won't Take "Yes" for an Answer: At one point Brian returns Stewie to normal, but reflexively reactivates the chamber due to the large number of failed attempts.
