The episode begins with a scene set five years in the past, where Amaryllis and her friends attempt to escape the clutches of the island chief on a boat. They are relentlessly pursued by Moz and Kirisame, the leader's loyal warriors. They possess a mysterious weapon capable of petrifying people, turning Amaryllis' companions into stone.

Amaryllis, who is at the other end of the boat, is only grazed by the petrification beam. Skillfully, she removes the part of her hair that has just turned to stone, halts the process, and manages to escape by jumping into the sea.

From this story told by Amaryllis, Senku draws conclusions about the petrification weapon and hypothesizes that it follows certain rules. Among the proposed properties of the petrification beam are a limited range, the need to throw it to activate it, and a chain reaction that can be interrupted if stopped quickly.

The narrative then shifts to Ibara, the island's minister, who wields significant power as the deputy commander. Meanwhile, Ginro, who was in the sea during the petrification attack, narrowly escapes the beam thanks to a precise arrow shot by Ukyo, which interrupts the weapon's trajectory. Thus, Ginro lands just outside the attack range and survives.

As the episode reaches its climax, Ibara and his men explore the ship and come across various unknown inventions. When they hear a strange noise, Ginro, who is hiding aboard the ship, risks being discovered. However, Suika distracts Ibara and his men with a clever diversion in the Green Room, saving Ginro from capture.