Ep. 4: Souichi and Kousuke encounter parachute drops while Kousuke kills his father and fights Ryouta.
Police arrest fourteen-year-old Kōsuke Kira for murdering three women. In the present, Souichi Natsume finds Kōsuke torturing frogs and attempts to explain morality, but Kōsuke rejects this. They witness parachute drops and investigate with Kōsuke’s father, Yoshihisa Kira. Flashbacks reveal Yoshihisa abused Kōsuke as a child. Yoshihisa forces Kōsuke to retrieve a supply case using bombs, then refuses to share it, citing survival of the fittest. Kōsuke kills Yoshihisa with a bomb, experiencing euphoria. Souichi flees, calling Kōsuke a monster, and meets Ryouta and Kiyoshi. Kōsuke pursues them, forcing Ryouta to fight. Ryouta cannot kill but recognizes Kōsuke as a Btooom! player. After hitting his head, Ryouta perceives reality as the game, defeats Kōsuke using sonar cancelling, and binds him. Ryouta takes the supplies and BIMs. Kōsuke learns Ryouta is the top Japanese Btooom! player.
Episodes
- Ep. 1 · Unemployed gamer Ryouta Sakamoto wakes on an island forced to play the real-life version of Btooom!
- Ep. 2 · Himiko’s traumatic past and survival on the island with Ryouta
- Ep. 3 · Ryouta encounters Kiyoshi Taira, who reveals the island's deadly chip-collecting game rules.
- Ep. 4 · Souichi and Kousuke encounter parachute drops while Kousuke kills his father and fights Ryouta.
- Ep. 5 · Ryouta investigates a cliffside attack by Himiko while uncovering the island's disappearance mystery.
- Ep. 6 · Ryouta and Kiyoshi survive komodo dragon attacks while Himiko regains consciousness.
- Ep. 7 · Ryouta confronts Masashi and Souichi while investigating Himiko's true identity.
- Ep. 8 · Sakamoto and Himiko encounter Shiki Murasaki while discussing survival strategies in Btooom!