The sixth episode of The WONDERfools begins with Gyeon-un suggesting to Ro-bin that they start a church similar to Dr. Ha's, promising a substantial amount of profit. However, his concern for Chae-ni grows, and he hurries off to speak with his mother. Outside, he witnesses Chae-ni being taken away and overhears Un-jeong discussing her powers with someone. Meanwhile, Ro-bin is happily preparing a meal for his friends, completely unaware of what's happening outside.
Meanwhile, Pal-ho, viewed as a savior within the cult, performs a miraculous feat by helping a disabled man walk again. The members of the Church of Eternal Salvation are stunned by this display and begin donating large amounts of money to the church. That night, Jun-mo tells Jeon-bok that Dr. Ha's people are operating the church and discusses the dangers surrounding it.
Elsewhere, Ho-ran is worried about Pal-ho's worsening arm condition. She attempts to speak with Dr. Ha but is stopped before reaching him. At the same time, Dr. Ha prepares Chae-ni for surgery and instructs the surgeons to sedate her so he can remove her heart. Chae-ni wakes up midway through the procedure and tries to escape, but she accidentally teleports back to Hawondo Lab on her own. Dr. Ha knocks her unconscious and later places her back on the operating table. When Chae-ni regains partial consciousness, Dr. Ha tells her that Jeon-bok is just as guilty as he is and asks her to sacrifice her life for the greater good.
Meanwhile, Gyeon-un rushes home and tries to relocate his family due to his fears for their safety. However, his wife refuses to trust him and instead asks him to report Chae-ni's kidnapping to the police. Gyeon-un is shocked after learning that his wife has accepted a massive order from the Church of Eternal Salvation. The argument leaves him emotionally overwhelmed and frustrated.
Elsewhere, Ho-ran uses her powers to brainwash Chae-ni into willingly sacrificing herself.
The following morning, Jeon-bok gets dressed and prepares to leave the house. Before leaving, she asks Ro-bin to save some food for Chae-ni and bring her home safely.
Soon thereafter, Gyeon-un's arrival brought a stark revelation to Ro-bin, revealing Un-jeong's treacherous betrayal. Enraged, Ro-bin insisted on their mission to rescue Chae-ni, the sole individual who had ever stood by his side during their school days. A vivid flashback unfolded, depicting Chae-ni bravely defending Ro-bin against school bullies.
In parallel, Jeon-bok paid a visit to Nam Sun-gyu's residence, only to discover that he had been admitted to a hospital. A subsequent call from Jun-mo revealed that Sun-gyu was actually at the Church of Eternal Salvation. Simultaneously, City Hall employees learned of Un-jeong's resignation as he quietly packed up his apartment.
Ro-bin's fury knew no bounds as he stormed into Un-jeong's apartment and engaged in a fierce battle, their powers clashing in a chaotic display. However, Ro-bin's concentration was shattered by a call from Gyeon-un, allowing Un-jeong to knock him unconscious. In the next moment, Un-jeong received a call from Jeon-bok, who urgently requested a meeting.
Meanwhile, Chae-ni consulted with Dr. Ha, questioning whether her sacrifice would truly aid Un-jeong. She felt a sense of relief upon hearing that her death would supposedly help him reunite with his mother.
Later, at Jeon-bok's house, Un-jeong perused Chae-ni's bucket list and reflected on her aspirations. Jeon-bok apologized for all that had transpired at Hawondo Lab and inquired about Chae-ni's whereabouts. Although Un-jeong refused to forgive Jeon-bok, he admitted that his betrayal of Chae-ni stemmed solely from his desire for information about his mother. Overwhelmed with guilt, he finally resolved to save Chae-ni.
In the meantime, Ro-bin and Gyeon-un tailed Un-jeong's movements. He requested Jeon-bok to gather 200 people and later visited City Hall to ask Seok-u for assistance. As Un-jeong studied a map of the Church of Eternal Salvation, plotting an escape route, he, Ro-bin, and Gyeon-un prepared to infiltrate the church and rescue Chae-ni.
At the same instant, Dr. Ha employs a sample of Chae-ni's DNA to bring a deceased rat back to life. In another part of the story, Pal-ho, Ho-ran, and Ju-ran engage in a discourse about the Child of Eternity, suspecting that Dr. Ha is concealing the truth about him. Ju-ran attempts to exert her powers over Dr. Ha to coerce an answer from him, but her efforts are futile as he remains unyielding. Instead, Dr. Ha urges her to continue placing her trust in him.
Meanwhile, a massive protest erupts outside the Church of Eternal Salvation, creating a chaotic scene around the premises. Pal-ho, Ho-ran, and Ju-ran attempt to manage the situation while Jun-mo covertly assists Un-jeong, Ro-bin, and Gyeon-un in sneaking inside. Jun-mo expresses gratitude to Un-jeong and reveals that he was one of the orphaned children saved from experimentation due to the fire ignited by Un-jeong years ago.
Elsewhere, Ho-ran tries to manipulate the police officers monitoring the protest, but Jeon-bok reminds the cops that the public has every right to protest peacefully. Within the lab, Un-jeong, Ro-bin, and Gyeon-un quietly subdue the guards as Dr. Ha commences surgery on Chae-ni to save Nam Sun-gyu.
Chae-ni realizes that she is being coerced into sacrificing herself to ensure the old man's survival. She adamantly refuses to die as Un-jeong enters the lab. Using his powers, he halts Dr. Ha's surgical endeavors on Chae-ni and rescues her. He also prevents the guards from launching an attack, while Ro-bin and Gyeon-un engage in a fight against them nearby.
Chae-ni finally regains full consciousness and thanks Un-jeong for his intervention. Un-jeong begs for forgiveness before kissing her to elevate her heart rate and activate her powers. He enjoins her to teleport them to a safe location.
However, just then, Pal-ho, Ju-ran, and Ho-ran arrive to attack Un-jeong, Ro-bin, and Gyeon-un. The episode concludes with Chae-ni returning to the church to lend a hand to her friends.
