The third season of Dr. Stone sees the Kingdom of Science facing a powerful enemy on Treasure Island and discovering the whereabouts of Why-Man.
Warning: This article contains heavy spoilers
Among Senku’s numerous inventions in the third season is a GPS. Instead of a satellite, this GPS uses a strong radio tower.
When the radio tower becomes operational, the Kingdom of Science receives a Morse code message consisting of a single word: “Why”.
This leads to the realization that there is someone out there who is using the same technology as them.
Senku and his friends start calling this person Why-Man and suspect him to be the mastermind behind humanity’s petrification.
The Kingdom of Science then builds a ship, Perseus, to sail to the other side of the world and find the source of the petrification beam.
However, Senku decides that their first destination will be the island where his father landed when he returned to Earth. Senku wishes to find his father’s space shuttle.
A select group of people embark on the Perseus to locate the space shuttle that Senku believes holds valuable minerals, such as platinum, necessary for producing the revival fluid.
Soyuz is one of Senku’s crew members. When he was a child, he was adopted by the people of the Ishigami Village after he washed up on the beach.
Soyuz is from Treasure Island, the place where the space shuttle is, and he offers to show them the way to his home.
When Senku and his crew reach the island, they come to know that the island’s master can petrify people using a scientific device, Medusa.
The crew infiltrates the Petrification Kingdom and tries to steal the device, but that is not an easy task when their opponent has a weapon as powerful as the Medusa.
Soon, Ginro discovers that the Master’s minister, Ibara, who conveys his orders to the people of the island, petrified the Master years ago.
Ibara now rules in the Master’s name. Ginro also comes to know that the Master was Soyuz’s father.
Senku and his crew then plan to revive the Master. However, the Master’s statue has been damaged way too much. He cannot be revived even if the statue is reassembled.
Despite that, Soyuz reassembles his father’s statue, and the crew is able to expose Ibara’s crimes by showing the statue to the island’s inhabitants.
Ibara then decides to petrify the whole island, but with the help of the rest of the crew, Senku avoids getting petrified.
As the only survivor, Senku fights Ibara for the Medusa, which can be activated by voice commands. During their final showdown, Senku uses the Medusa to petrify Ibara.
Once Senku wins, he revives his friends one by one. When he contacts Ruri using their telephone, their conversation is interrupted by Why-Man.
Why-Man tries to give a command to the Medusa to petrify the whole planet. Additionally, Why-Man uses a computer-generated voice to sound like Senku.
The crew also revives a statue that has a Medusa tattoo. The revived man is Matsukaze, who becomes Ginro’s bodyguard, as Ginro resembles his previous master.
Hundreds of years ago, Matsukaze was petrified along with the rest of his village when several Medusas fell from the sky.
Senku then tracks down Why-Man’s signal and learns that the Moon is the only place where he can be. To catch him, Senku’s next step is to launch an assault on the Moon.
Soyuz becomes the new master of the Petrification Kingdom. With him as the Master, the Petrification Kingdom is now an ally of the Kingdom of Science.
Soyuz asks Kirisame, one of the strongest warriors on the island, to accompany Senku’s crew and help them on their next mission.
After constructing a radio tower on Treasure Island, Senku and his crew, along with Kirisame and Matsukaze, return to Ishigami Village to prepare for their next adventure.
The return of the strongest warrior
Senku cannot take all his friends to the Moon. A small crew comprising a pilot, a scientist, and a strong warrior is needed.
Senku will be the scientist and Ryusui will be the pilot. To launch an assault on the Moon, Senku needs their strongest warrior, who is none other than Tsukasa.
After returning to Ishigami Village, Senku goes to wake Tsukasa. The only problem is that the Medusa is running out of battery.
Senku and his friends hope that the device will function one more time. They use the Medusa on Tsukasa, and it works, much to their relief.
They then revive Tsukasa, and he returns as strong as ever. Senku now has the warrior who will join him on his journey into space.
The Kingdom of Science unites
Senku tells Tsukasa about his plans. Initially, he is surprised, but he understands why Senku needs him to go with him.
As Senku was not petrified again, he is the only one with cracks. There is no way to get rid of his cracks, so his friends decide to draw cracks on their faces in a show of solidarity.
Gen persuades Tsukasa to do the same, and by drawing scars on his face, Tsukasa finally joins the Kingdom of Science.
Having Tsukasa as an ally gives everyone the confidence that they can win against Why-Man, no matter how strong he is.
Tsukasa also admits to Gen that he used to believe that reviving him was his biggest mistake, as Gen betrayed him, but he no longer believes that and is glad to have him around.
Voyage to establish new cities
In order to gather the materials that he needs to go to the Moon, Senku needs to travel to different places.
Now that the Petrification Kingdom is an ally, Senku can make as much revival fluid as he needs, so he also plans to revive statues and build cities all over the world.
Ukyo worries that reviving so many people can be a problem, as not everyone will accept the social order they have established.
However, Tsukasa assures them that it would not be a problem, as they have someone as strong as him on their side.
To revive billions of people, Senku needs plenty of alcohol to make revival liquid, so their next destination will be Corn City, which used to be America.
Yellow Dent is a corn variant with a high yield that is found there. It can be used not only to produce alcohol for the revival fluid but also as a food source for the people who will be revived.
The third season ends with Senku and his crew setting sail once again, marking the beginning of the voyage to establish new cities.
Also Read: Petrification device in Dr. Stone explained