When he was in primary schools, his older brother was a kind and admired figure. After witnessing his brother's mysterious death, Ryuhei is now a lively high school student who doesn't feel the nightmare around him. On the night he is bitten by the mysterious creature Tris, he has an unusual dream. A group of black-clad youths are battling a strange creature. Ryuhei, who is at the mercy of a mysterious phenomenon, finally sees the monster in real life in Shibuya.

The pattern that appeared on the forehead of the top gamer responsible for the mysterious incident in Shibuya was the same as the one left at the scene of Ryuhei's brother's murder. Jessica and Nukuto were the ones who were fighting. One day, Ryuhei's childhood friend, Tris, explains to him that the creature is a "Weird". One day, Reina, Ryuhei's childhood friend, sees her classmate Airi, who is different from usual.

A "knocker-upper" is someone who has awakened to the ability to destroy the weirds that appear from nightmares. When Reina is discovered by Tris to have this ability, Ryuhei asks Reina to help him solve the mystery of her brother's death, as he thinks that the rumoured Somnium Drop candy in town and the sign of a mysterious incident have something to do with it. At the same time, Reina, who is popular on social media, gets into unexpected trouble.

Despite being a primary school student, he is an excellent knocker-upper. In front of everyone, he is mature and cocky, but always cheerful. But in his eyes, Ryuhei sees a shadow he shares with himself. They fight together against the Weird, but they don't know much about each other. Ryuhei can't leave him alone, so he expresses his feelings to him.

Fighting isn't all there is to it. Thanks to Ryuhei's quick thinking and energy, the Knocker-ups are now one step closer to each other. Under Jessica's direction, they once again analyze and investigate who they should fight with their abilities. The purpose of the enemy, the Somnium Drop, and the voice Airi heard, who is it? Then, news of a sad incident comes on the street.

More than ever before, there have been many incidents involving "Yumemite", those who are drunk on Somnium Drop. A mysterious cult based in Shibuya, which Nuto has investigated. What are the intentions of this group that is moving even bigger? In the middle of the battle, Reina notices the existence of a girl. She still has her memories of "Desaria" and appeals to Ryuhei and the others that she is related to the cult and wants to help them.

After meeting Rando and Eru from the everlasting summer island of Yura, Ryuhei and his friends learn that the island is not unrelated to the Shibuya incident. Ryuhei and Rando's strong feelings for their hometown cause them to clash over something, and when Desaria appears, he and Eru are isolated in an elevator. During their brief respite from the battle, Ryuhei is shocked to hear the name "Kazuhazuka" in the old island legend of the "dead man's return" told by Eru.

Ryuhei learns that his brother's dying message has a connection to the evil that once ruled the earth and is depicted in Yura Island's ancient documents and prehistoric murals. While battling the Weird, life goes on slowly, and it is time for career guidance at the high school. At the same time, a mysterious phenomenon occurs that Ryuhei, Reina and Airi cannot resist.

After Kazuha's death, Yumemite, who offers wishes to the evil one, starts to appear around Ryuhei as he approaches the shadow of the cult. One day, Ryuhei is elated to find a letter in his shoe box, and Reina and her friends are suspicious of his old-fashioned approach. After piecing together this fun situation, Ryuhei learns a fact he never imagined and runs off without a second thought.

It was his best friend Murase who was handing out Somnium Drops to the students around him. Just when Ryuhei thinks he has been betrayed, a masked man from the cult appears and defeats him with a single blow. Unable to shake off the awe of his overwhelming power, Ryuhei reminisces about his days with his brother Junpei, who was killed by the man. And with the help of Rando's words, he arrives at the fact that his brother was connected to Troy Merai.

When Murase confronts Ryuhei, he urges him to drink the Somnium Drop in order to reach his desire - the Lord of the Faith. Without a doubt, Ryuhei drinks the drop and finds the Lord of the Faith in Troy Merai's inner castle, but what emerges from beneath the mask is the face of his older brother, Junpei. He whispered to him to offer a wish with his brother's face. Reina and the others come to save Ryuhei by drinking the drop. When Ryuhei is in danger, Reina is the one who offers her wish without any pretense.

Weirded Reina makes a wish, and Desaria appears in the city of Shibuya. The time of the Star Dragon has come, and the evil god Kutrowag has returned. Rando and Eru rush to the scene of the greatest crisis, but their feelings about what to protect intersect, and Ryuhei, who wants to protect Reina, is unexpectedly seriously injured.

Will Ryuhei, Reina, Airi, Jessica, and Nukuto wake up from this nightmare, as they awaken as Knocker Up and continue to fight Weird in secret?