BMO Noire

"BMO Noire" is the seventeenth episode in the fourth season of Adventure Time.

Synopsis
BMO tries to solve the mystery of Finn's missing sock.

Plot
Finn asks Jake where his sock is, but Jake denies taking it. They get into an argument when Finn asks Jake to help him look for it. At this point the colors change to black and white (like an old movie). BMO decides to find Finn's missing sock. Jake convinces Finn to go out with only one sock and BMO snaps a picture of Finn's foot as he leaves.

BMO notices Ronnie in the picture and grabs him for questioning. BMO spots lipstick on the back of Ronnie's neck and asks him about Lorraine. Ronnie warns BMO to stay away from her, but BMO assures him that they are "dinosaur bones." Ronnie then denies taking the sock, but points out a stain on Finn's other sock in the photo, saying that it looks like a grape juice stain. BMO goes into the pantry to check out the grape juice but it finds it's unopened and realizes Ronnie was lying. Suddenly, someone traps BMO by shutting the door. When the door opens, Officer Davis is standing there waiting for BMO. He tells BMO to stay out of police business and threatens to put BMO behind bars.

BMO, ignoring Officer Davis' advice, heads over to Lorraine's hoping that she can lead BMO to Ronnie. BMO asks Lorraine where the sock is, but she denies knowing anything about it. When BMO suggests that Ronnie took it, she laughs at the idea, saying that if Ronnie were man enough to take a sock she wouldn't be spending her nights with Bebe. BMO catches Lorraine mentioning that the sock is Finn's and points out that she shouldn't know any details of the case. Lorraine confesses that Bebe was the one who stole the sock. As BMO is leaving, Lorraine asks BMO not to tell Ronnie about her and Bebe, but Ronnie is hiding near the rafters.

BMO heads to Bebe's, a dance club downtown, and immediately starts stepping on Bebe and grilling him about the sock's location. Bebe denies knowing anything about socks, so BMO grabs some soot from a furnace and smears it on Bebe telling him that Lorraine sold him out. Bebe denies it and tells BMO that it was Ronnie who took the sock. BMO goes to wash the soot off of its hands, but when BMO gets back Bebe is dead and the police are arriving. BMO runs from the cops, but trips over one of them and falls down the Tree Fort's ladder, hitting its head.

While unconscious, BMO has a strange dream/vision which consists of POV sequences of BMO performing the actions of the 'characters' in the 'play'. BMO wakes up to find Neptr next to it. BMO asks Neptr if he had seen any cops down there. Neptr tells BMO that only they and Ronnie had been down there all day and that "about a socks-worth" of treasure was missing from that room. BMO realizes that Ronnie took the sock to carry the treasure, killed Bebe so he wouldn't tell anyone, and pinned it on BMO.

BMO goes back upstairs to look for Ronnie, but finds a chalk outline of Ronnie with a ketchup stain in it instead. Officer Davis tells BMO that it is off the hook since they know Ronnie killed Bebe and took the treasure. Officer Davis hands BMO the confession Ronnie left and tells BMO to let the case go. BMO then notices that the note was written with lipstick and runs outside.

Lorraine is sitting on top of a barrel, with treasure, and floating in a pond. Lorraine confesses to framing Ronnie and Bebe and then reveals that the sock is in her and BMO's "secret grown-up kissing spot," to which BMO reacts with a giggle. Lorraine bids farewell, floats to the opposite side of the pond and jumps on to land.

The colors change back to normal as Finn and Jake return to the Tree Fort. BMO shows Finn that his sock was in his pillow the whole time.

Main characters

 * BMO
 * Ronnie
 * Lorraine
 * Officer Davis
 * Bebe

Minor characters

 * Finn
 * Jake
 * Neptr
 * Officer Meow
 * Lieutenant Whiskers
 * Snail

Trivia

 * During BMO's dream sequence, its face becomes human-like - resembling the detective's face in the title card.
 * This is the first Adventure Time episode that is in black and white, but this is not the first time Adventure Time showed a scene that was black and white. The first time was in "Hug Wolf," when BMO used strobe light mode.
 * This is the first episode where BMO is the main character.
 * This is the third time Finn is a minor character.
 * This is the second episode where the title picture is revealed in the preview, first being "Gotcha."
 * This is Neptr's third appearance in Adventure Time and second in season 4.
 * The Tree Fort has cats and a chicken coop.
 * All of the new characters shown in this episode are voiced by Niki Yang, the same voice for BMO and Lady Rainicorn.

Cultural references

 * "BMO Noire" is a reference to the concept of film noir (French for "black film"), a genre of crime movies popular in the 1940s and 50s.
 * The episode uses conventional elements of film noir including: black-and-white photography, contrasting light and shadows, the use of voiceover narration, smoking, double cross, wrongly accused people, flashbacks in a knockout sequence, swarthy characters including a femme fatale, and the protagonist of the story being a hardboiled detective.
 * When BMO took off its controller plug and stepped on it, there was the sound of a cigarette being extinguished. This is common imagery from generic crime movies and hardboiled detectives.

Episode connections

 * This is the fourth time Adventure Time has had a mystery episode. The first was "Mystery Train," followed by "The Creeps" and "Apple Thief."
 * This is the second time Jake is seen with make-up, first being in "Tree Trunks."
 * This is the third time that both Finn and Jake are minor characters, the first time being in "Fionna and Cake," and also in "Thank You."

Errors

 * BMO finds Finn's sock hidden inside his pillow. But in the next scene, you can see Finn wearing both his socks while BMO is still holding the one Finn couldn't find.
 * When BMO punched the mirror, the reflection of the word "BMO" is the same where it should be an inverted "BMO."

Production notes

 * The working title for this episode was "B-Mo Noir." So technically, only the spelling changed.

Videos
Adventure Time - B-Mo Noire (long preview)|The extended preview. "BMO Noire" Animatic|Animatic.