The episode starts with a TV program called Judgement Day, where the commenter explains they are going to be judging the Anarchy sisters. Upon welcoming them, he asks them how they feel; naturally, Panty and Stocking reply that they'll rather not be there at all. Their fans go crazy, but the commenter declares that not everyone in the public are fans; indeed, a large section of the audience is waving anti-angel signs and chanting "No more Panty! No more Stocking!". The commenter proceeds to introduce their prosecutor: Tom Croose, who mourns for his friend and vows that the angels will pay for their crime - killing an innocent ghost.
The commenter summarizes the case by reviewing the life of the victim, a doglike ghost named Husband Petter. Despite being a ghost, he was surprisingly cheerful and good-hearted, becoming the first Ghost recognized as a citizen of Daten City, and happily married to another of his anomalously non-violent kind. However, on November 27th, he was found dead in Central Park, and the Anarchy sisters are the prime suspects for his murder. As the commenter finishes the story, Tom Croose solemnly declares that it is a tragic tale, but the angels simply ask if he can prove their involvement.
Before the trial can begin, the angels are given a chance to choose an attorney from one of three boxes; the oldest lawyer in the world, the cheapest lawyer in the world, and the lawyer with the highest IQ in the world. After the host assures them that the show doesn't lie, Panty and Stocking choose the third box - only to meet a monkey named Mr. Abrams. The host explains that Mr. Abrams is a certified attorney, and the smartest lawyer in the monkey world. The angels demand to know how the monkey is supposed to defend them, but Mr. Abrams reveals that he can speak perfectly, thanks to a machine on his head which translates his thoughts into speech.
With the judge presiding, the trial commences, and Tom Croose begins asking the Anarchy sisters a few questions. He reveals that Panty and Stocking were only five minutes away from the crime scene, making it quite possible for them to be the murderers. He proceeds to ask Panty what she would do if she saw a rampaging ghost. Panty responds she would shoot it - however, Tom Croose only whispered the "rampaging" part, and uses her response to imply that the angels would not think twice about killing even the most innocent of ghosts. When Stocking protests, Tom Croose produces several pictures of ghosts destroyed by the angels and asks if Stocking remembers their names. Stocking and Panty point out that they would never have a chance to learn a Ghost's name in the heat of battle, which Tom Croose explains is why they don't recall killing Husband Petter.
The prosecutor then presents the judge with Panty's panties, explaining that they are her main weapon. He asserts that witnesses at the scene of the crime heard gunshots in Central Park, which implicates Panty, as her underwear can transform into a gun. To prove his point, he asks Panty to demonstrate - despite the latter's reluctance, Stocking suggests that she just get it over with. The blonde angel starts pole dancing for the audience, reciting her usual chant, but the judge soon stops her, outraged that Panty would desecrate the courtroom with her lewd acts. As a consequence, Panty and Stocking are trapped inside iron maiden-like cases that only leave their faces exposed. Mr. Abrams begins trying to grab Panty's exposed bangs, thinking them to be bananas; meanwhile, Tom Croose calls Wife Petter to the stand, where she breaks down into tears, begging for her husband to return to her.
With that done, the commenter asks for everyone's verdict regarding the case, and everyone votes for the angels to die. Accordingly, Panty and Stocking are electrocuted through their restraints; when the initial shock proves useless, the commenter signals someone to heighten the power of the electrocution machine. It is then revealed that the commenter and Tom Croose are Scanty and Kneesocks in disguise - the entire trial is a front for them to finally be rid of the angels.
The electrocution machine eventually overloads before it can kill the Anarchy sisters; in the smoky aftermath, Mr. Abrams finally grabs Panty's bangs. Upon touching Panty's electrified hair, the monkey receives a powerful shock of his own, causing his thought translator to malfunction. As Stocking begs for another lawyer, the helmet falls to the ground, and Mr Abrams gets to his feet, now possessing incredible intelligence. He objects to the prosecution's argument, pointing out that Husband would have left no remains if he had been killed by angelic weapons. Furthermore, large fang marks were found on Husband's body - thus, Mr. Abrams declares that the true culprit was none other than Wife!
Faced with this evidence, the audience turns on Wife, electrocuting her with the same force as the angels. Unhinged by the shocks, Wife confesses her crime, revealing that she was only playing the part of an innocent to protect herself. Deriding Husband's unwillingness to destroy humanity, she mutates into a four-jawed monster and attacks the judge - meanwhile, Mr. Abrams grabs the commenter and Tom Croose, using a residual electricity within him to shock them and remove their disguises.
Exposed and infuriated at another failure, Scanty and Kneesocks flee, leaving the judge to beg Panty and Stocking to destroy the rampaging ghost. The angels feign reluctance, citing the judge's own disapproval of their actions, but the desperate man redacts his earlier statement and frees the sisters from their restraints. With palpable amusement at the situation, Panty and Stocking transform their garments and quickly finish off Wife Petter, to raucous applause from the crowd. Bidding viewers farewell, Panty and Stocking declare that justice always prevails - shortly before Mr. Abrams rips off the former's bangs and stuffs them into his mouth.
The episode's title is a reference to the American drama film, 12 Angry Men.
One of the characters, named Tom Croose, is an obvious reference/parody to celebrity Tom Cruise. His appearance and role as an overdramatic prosecutor is based off of Tom Cruise's character in the film Magnolia.
When Mr. Abrams' brain was being supercharged, rainbow-colored lines of light were shown spreading through his brain. This is a reference to Tengen Toppa Gurren Lagann, where technical readouts of Lagann combining with other mecha would have a similar animation of glowing lines spreading through a silhouette of the other mecha.
When Scanty and Kneesocks are talking about creating the false charge, they mention being outwitted by a monkey. Right after Kneesocks mentions being outwitted by a monkey, a quick lightning bolt comes down the middle of his face with a figure in the lightning. The figure may resemble Matilda Ajan from Mobile Suit Gundam. The “lightning bolt” is a reference to Mobile Suit Gundam, where certain characters, known as New Types, Six Sense activates (a lightning bolt will come down the middle of their face).
Mr. Husband Petter and Mrs. Wife Petter resemble the characters from the American cartoon, Ren and Stimpy.
The phrase "justice always prevails" is a Case Closed reference.
After Mrs. Wife Petter transformed, she resembled the Thing's canine form.
When killed, her scream of "Carpenter!" references the director of the movie, John Carpenter.