The episode begins with the boys--Stan, Kyle, Cartman, and Kenny--at school, where they are discussing the upcoming school play. The play is a rendition of "The Lion King," and the boys are excited about their roles. Stan is particularly enthusiastic about the production, while Cartman is more focused on how he can manipulate the situation to his advantage.

As the boys prepare for the play, they encounter a problem when they discover that the school has decided to cast a new character, a penis, in the production. This decision is met with confusion and disbelief from the boys, especially from Stan and Kyle, who are concerned about the implications of having a penis character in a children's play. Cartman, however, sees this as an opportunity to create chaos and stir up controversy.

The scene shifts to the boys rehearsing for the play. During a rehearsal, the penis character is introduced, and the boys react with shock and laughter. The absurdity of the situation escalates as the penis character begins to overshadow the main characters, leading to frustration among the boys. Stan and Kyle express their discontent, while Cartman revels in the attention the penis is receiving.

As the play approaches, the boys decide to take action against the penis character. They brainstorm ways to sabotage the play and eliminate the penis from the production. Their plans become increasingly elaborate and ridiculous, showcasing their desperation to regain control over the play. Meanwhile, Cartman continues to plot his own scheme, aiming to use the penis character to his advantage.

The day of the performance arrives, and the boys are filled with a mix of excitement and anxiety. The auditorium is packed with parents and students, all eager to see the play. As the performance begins, the boys struggle to focus on their roles, constantly distracted by the penis character's antics. The audience reacts with laughter and confusion, further fueling the boys' frustration.

During a pivotal moment in the play, the penis character steals the spotlight, leading to a chaotic scene on stage. Stan and Kyle attempt to regain control, but their efforts are thwarted by Cartman's manipulations. The situation spirals out of control as the boys argue and bicker, leading to a comedic yet chaotic climax.

In the final moments of the play, the boys come together to confront the absurdity of the situation. They realize that their attempts to eliminate the penis character have only made things worse. In a moment of unity, they decide to embrace the chaos and incorporate the penis character into the finale of the play, leading to an unexpected and humorous conclusion.

The episode wraps up with the boys reflecting on the experience, acknowledging the ridiculousness of the entire situation. They share a laugh over the events that transpired, solidifying their friendship despite the chaos that unfolded during the play. The final scene shows the boys leaving the auditorium, still chuckling about the absurdity of the penis character and the play as a whole.

In the ending of "Eek, A Penis!", the boys of South Park are faced with the chaos that ensues after a series of misunderstandings regarding a supposed "penis" that has been spotted in the town. The episode culminates in a confrontation where the boys realize the absurdity of their fears and the situation. Ultimately, they come to terms with the ridiculousness of their panic, and the episode ends with a humorous resolution that highlights the boys' friendship and their ability to navigate through bizarre circumstances.

As the episode progresses towards its conclusion, the scene shifts to the boys gathering at the school, where they are discussing the recent events surrounding the mysterious penis sightings. Stan, Kyle, Cartman, and Kenny are all visibly anxious, their expressions a mix of confusion and fear. The atmosphere is charged with tension as they recount the various rumors that have spread throughout South Park, each boy contributing to the escalating hysteria.

In the next scene, the boys decide to take matters into their own hands. They form a plan to confront the supposed threat, which they believe is a monstrous penis that has been terrorizing the town. Their determination is palpable, and they rally together, showcasing their camaraderie despite the absurdity of the situation. The boys' motivations are driven by a mix of bravery and the desire to protect their community, even if the threat is entirely fabricated.

As they venture out into the town, the boys encounter various townsfolk who are also caught up in the panic. The visual chaos of the town is evident, with people running in all directions, shouting about the penis. The boys' interactions with the townspeople reveal their growing frustration and confusion, as they try to make sense of the hysteria that has gripped South Park.

The climax of the episode occurs when the boys finally confront what they believe to be the source of their fears. In a dramatic moment, they come face to face with a large inflatable penis that has been mistaken for a real threat. The absurdity of the situation hits them all at once, and the tension breaks as they realize how ridiculous their fears have been. Laughter erupts among the boys, and they share a moment of relief, recognizing the humor in their panic.

In the final scenes, the boys return to their normal lives, their friendship strengthened by the experience. They reflect on the events with a sense of camaraderie, joking about how they let their imaginations run wild. The episode concludes with a humorous twist, as the inflatable penis is revealed to be part of a local festival, further emphasizing the absurdity of the entire situation.

By the end of the episode, Stan, Kyle, Cartman, and Kenny have all learned to navigate the chaos together, showcasing their resilience and the strength of their friendship. Each character returns to their usual antics, but with a newfound appreciation for the ridiculousness of their fears and the importance of sticking together in the face of absurdity.

In the episode "Eek, A Penis!" from season 12 of South Park, there is no post-credit scene. The episode concludes without any additional content after the credits roll. The focus remains on the main storyline, which revolves around the boys' reactions to a new school policy regarding the use of the word "penis" and the ensuing chaos that follows. The episode wraps up with the resolution of the main plot, leaving no further scenes or jokes after the credits.

In 'Eek, A Penis!', Mr. Garrison undergoes a sex change operation to become Mrs. Garrison, but his penis is later revealed to have developed a mind of its own and escapes, leading to a series of chaotic events.

The boys, particularly Stan and Kyle, are initially confused and disturbed by Mr. Garrison's transformation into Mrs. Garrison, leading to humorous and awkward interactions as they try to process the change.

Mr. Slave, who is Mr. Garrison's former partner, plays a significant role as he helps Mr. Garrison adjust to his new identity and later becomes involved in the chaos surrounding the runaway penis.

The town is thrown into a frenzy as the runaway penis causes havoc, leading to panic and absurd situations, showcasing the town's exaggerated and comedic response to bizarre events.

The penis having a mind of its own serves as a comedic device that explores themes of identity and autonomy, while also providing a satirical take on gender and sexuality, as it interacts with various characters throughout the episode.

"Eek, A Penis!" from South Park's twelfth season is not family-friendly and contains several potentially objectionable elements. Here are some aspects that might be upsetting for children or sensitive viewers:

1. Graphic Humor: The episode features explicit jokes and visual gags related to male anatomy, which may be inappropriate for younger audiences.

2. Sexual Themes: There are discussions and scenarios involving sexual content and innuendos that are not suitable for children.

3. Violence: The episode includes scenes of violence, including characters being harmed in exaggerated and comedic ways.

4. Dark Humor: The show often employs dark humor that can be unsettling, particularly in how it addresses serious topics in a satirical manner.

5. Language: There is the use of profanity and crude language throughout the episode, which may not be appropriate for younger viewers.

These elements contribute to the overall tone of the show, which is known for its irreverent and controversial approach to various subjects.