The seventh episode of The WONDERfools unfolds with Jeon-bok filing a complaint at the police station about the unlawful experiments occurring at the Church of Eternal Salvation. Meanwhile, Ho-ran employs her powers to distract Un-jeong during the ensuing skirmish. Un-jeong is transported back to the fateful night that led to the demise of the Child of Eternity. Ho-ran angrily blames him for their collective anguish and pain, leaving Un-jeong visibly shaken.
In parallel, Pal-ho attempts to eliminate Ro-bin and Gyeon-un, but Ro-bin manages to thwart his efforts. Ro-bin endures Pal-ho's onslaught for as long as possible before unleashing a powerful punch that sends him reeling. Elsewhere, Un-jeong's powers wreak havoc in the church basement, causing a violent tempest. Gyeon-un utilizes his abilities to hold onto Ro-bin and Chae-ni after she returns to the church.
Chae-ni manages to snap Un-jeong out of Ho-ran's hallucination, leaving him reeling from a nosebleed and blaming himself for the loss of the Child of Eternity. Chae-ni empathizes with him and tries to calm him down, but she soon realizes that his powers are waning. She decides to teleport Un-jeong, Ro-bin, and Gyeon-un away from the church. However, Gyeon-un is inadvertently left behind due to his deceptive behavior during the process. As Pal-ho slowly regains consciousness, Gyeon-un begins to worry about his safety.
Dr. Ha injects Sun-gyu's body with Chae-ni's blood, and before the experiment commences, Sun-gyu orders his guards to eliminate Dr. Ha and the doctors if anything goes awry. Almost immediately, Sun-gyu's body begins to reverse its age and transform into a younger version of himself. However, the effects wear off within seconds, causing him to rapidly age again until his body rots away and he dies instantaneously.
Chae-ni watches the experiment in secret from outside the lab and is horrified by what she witnesses. Ju-ran uses her powers to brainwash Sun-gyu's guards and forces them to leave the lab. Despite Sun-gyu's demise, Dr. Ha insists that the experiment was still a success and tells Pal-ho and Ju-ran that he remains hopeful. He demands more of Chae-ni's blood, which terrifies her.
Pal-ho immediately sets after Chae-ni, but she swiftly bites into a coffee jelly and teleports away. She suddenly reappears in the midst of a church service. Dr. Ha orders Pal-ho to find her while Ju-ran is concerned that Pal-ho is growing weaker due to the rot spreading through his hand, fearing it could eventually reach his heart and kill him.
However, Dr. Ha ignores their concerns and manipulates Ju-ran and Pal-ho into continuing their fight for the so-called greater good. Outside, Pal-ho scolds Ju-ran for making him appear weak in front of Dr. Ha. He reveals that Dr. Ha gave him a device to protect him from Ju-ran's brainwashing powers. Ju-ran realizes that Dr. Ha does not trust her either and becomes upset. Pal-ho tells Ju-ran to continue believing in Dr. Ha before leaving to search for Chae-ni. Ho-ran overhears their conversation and feels isolated after realizing that she has no one left to rely on now that Un-jeong has chosen Chae-ni and her friends over her.
Elsewhere, Chae-ni erupts into a fury against the followers of the Church of Eternal Salvation, railing against their wasteful expenditure of hard-earned money on a cult that utilizes donations for illegal experiments. However, Ju-ran exerts her influence over the congregation, compelling them to launch an attack on Chae-ni, her friends, and the protestors gathered outside the church.
The brainwashed mob charges toward Chae-ni, but Un-jeong employs his powers to shield her. He urges Chae-ni to leave the church with Ro-bin and Gyeon-un, but she stubbornly refuses to abandon him while he's still under assault. Meanwhile, Jun-mo informs Jeon-bok of a sense of unease at the church. Jeon-bok orders him to proceed with Plan B, and Jun-mo promptly instructs his teammates to prepare for an assault. Simultaneously, Gyeon-un's wife and daughter express their concerns for his safety.
Gyeon-un himself uses his powers to cling to the basement ceiling as Dr. Ha's men dispose of Sun-gyu's body and the corpses of his guards. From above, Gyeon-un overhears Ho-ran and Ju-ran discussing Dr. Ha's sinister plan to spread chemicals throughout the city as part of an apocalypse scheme. Terrified for his family's safety, Gyeon-un attempts to escape the church facility.
As Un-jeong, Chae-ni, and Ro-bin take refuge inside a room, they soon confront Pal-ho once again. Un-jeong tells Chae-ni to teleport Ro-bin to a safe location and promises to retrieve him later. Pal-ho and Un-jeong engage in a brutal fistfight, while Chae-ni teleports Ro-bin to his apartment before arming herself for the return to the church. The battle between Un-jeong and Pal-ho escalates in violence until it culminates in a devastating explosion.
Outside, Gyeon-un runs straight into the path of the brainwashed churchgoers chasing after him, but Chae-ni arrives with a chainsaw and shields him from harm. She rushes back toward the church to save Un-jeong but is horrified by the destruction surrounding the area.
Chae-ni is filled with desperation over Un-jeong's fate, but Gyeon-un explains Dr. Ha's apocalypse plan to her. He urges her to flee before the chemicals are released across the entire city. At the same time, Pal-ho dies in Ju-ran's arms, and the church followers mourn the loss of the man they once believed to be their savior. Elsewhere, Un-jeong is badly wounded but still manages to make his way toward the lab where Dr. Ha awaits, as the episode concludes.
