'''Airdate:''' May 2, 2010

Brian and Stewie are at the bank with Brian putting money in his safety deposit box. Just as they’re about to leave, the bank closes and the vault’s doors close, leaving them trapped. It gets worse when Stewie gets scared by the doors closing and defecates in his diaper. Stewie tells Brian that he’ll get a rash if his poop isn’t removed and asks him to eat his poop. Brian refuses to do so, but then realizes that Stewie has his cellphone with him, which is low on battery. But rather than calling for help, Stewie calls a store to return a $3,000 sweater he bought. After the phone dies, Brian is furious at Stewie and slaps him across the face, which leaves Stewie to cry in the corner. Feeling bad for what he did, Brian reluctantly agrees to eat Stewie’s poop, followed by wiping Stewie’s butt by licking it. After he does it, the two decide to settle down and sleep, but realize that they’ll be stuck in the vault even longer because tomorrow is Sunday.

The next day, Brian decides to take a bottle of scotch from his deposit box and Stewie joins in in drinking and dancing with him. While drunk, Stewie asks Brian to pierce his ear, which Brian does, but the pin gets stuck and results in Stewie getting a big, bloody hole in his ear. Stewie, still drunk, asks Brian about Cesar Millan, to which Brian says that dogs always live in the moment. Brian feels offended when Stewie says that he doesn’t live with purpose, to which Stewie rebuffs that he only made him eat his poop because it would amuse him. Horrified, Brian aims a gun from his deposit box at Stewie so he can kill him, but Stewie points out a security camera in the vault and Brian learns to his horror that his disgusting ordeal has been caught on tape. Stewie tries to give Brian a mercy kill with his gun, bit instead fires a bullet that ricochets all over the vault, while hiding from the bullet, the two apologize to each other.

Later that night, Stewie takes some energy bars from his backpack and Brian reprimands him for keeping food from him. Stewie gives him a bar and the two settle down. Stewie asks why would Brian have a gun with him when he’s always spewing liberal rants of stricter gun control. After some hesitation, Brian admits he’s suicidal, saying Stewie is right that he doesn't have a reason to live, like other dogs do, and the scotch is there so he can have one last drink before he shoots himself in the head. Stewie cheers him up by saying that he gives him purpose and that he’s his only friend. Brian thanks Stewie for being his friend and he reads ''David Copperfield'' to Stewie while he falls asleep. The next morning, the vault’s door open and Brian carries a sleeping Stewie out.
!!"Brian & Stewie" contains examples of:
* BorrowedCatchphrase: At one point, Stewie says "Giggity".
* BottleEpisode, VerySpecialEpisode, and SomethingCompletelyDifferent: It's the only ''FamilyGuy'' episode (so far) to have no cutaway jokes, flashbacks, or any of the typical ''FamilyGuy'' humor (besides [[spoiler: the infamous diaper-eating sequence]]) nor does it have any other voice actor besides SethMacFarlane, or any music or musical numbers (though when it first aired as part of the "FOX Rocks" line-up, the episode immediately after that was a ClipShow of the series' different musical numbers), it takes place in one setting (SethMacFarlane has stated that he wanted to do this episode like a ''WaitingForGodot''-style play), and is one in a handful of episodes that's more dramatic than funny (see also: "Screams of Silence: The Brenda Q. Story," "Brian Wallows and Peter's Swallows," and "Partial Terms of Endearment").
* {{Bowdlerization}}: On the TV version, a lot of the "Diaper-eating scene" and references to it had to be edited (and, like most other ''FamilyGuy'' episodes, the uncut version -- with the original lines and unbleeped swearing -- can be found on DVD).
* DrivenToSuicide: It's revealed Brian has a gun so he can kill himself because he feels his life is not worth living.
* IronicEcho: "Oh I'm just callin' like I'm seein' it!"
* OhCrap: When Brian realizes that his acts of eating Stewie's poop and licking his butt have been caught on tape by a security camera.
* SickAndWrong: Brian in regards to Stewie asking him to eat his poop.
-->'''Brian:''' That's ''sick!'' That is sick! How messed up in the head are you that you'd even ''ask!?''
* SkewedPriorities: Stewie's cell phone had just enough battery life for one call... which he wastes trying to return his sweater.
* WhamLine: Brian's admission that he keeps a gun for if he ever wants to kill himself comes fresh off of Stewie making perverted jokes about it. The line becomes HarsherInHindsight given the events of "The Life of Brian" (only Brian dies after someone runs him over).
* YouMonster: Brian says this when Stewie reveals that he made him eat his poop because [[ItAmusedMe it amused him]].
-->'''Brian:''' You son of a bitch, it could kill you for that!