Dr. Stone Science Future Part 3 Episode 3 Review: All Plot, No Filler

Credit: TMS Entertainment

Dr. Stone Science Future Part 3 released its third episode on April 16, 2026, and as the title suggests, the pace is once again picking up speed. While the second episode felt a bit slow (though not in a bad way), the current speed of events effectively conveys the urgency of building a rocket.

This episode revealed another character who had been teased for a long time, and he happened to be the older brother of one of the anime’s best characters. Now that the Science Kingdom has a genius mathematician, the invention of computers isn’t too far off. Let’s dive into the review with a small recap.

The Science Kingdom Sets Foot In India

Ryuusui from Dr. Stone | Credit: TMS Entertainment

In the previous episode, Senku made a ballistic missile to clear the Suez Canal and successfully made his way towards India along with Ryuusui, Chrome, Kohaku, and others. This new episode picked up straight after that, but skipped the journey – the science kingdom was already in India.

Furthermore, the episode didn’t waste a single minute, as they immediately started gathering materials and making a plan on finding Sai, who Ryuusui defines as one of the greatest mathematicians of all time. Senku and Chelsea Childe immediately located Sai’s body with the help of the information Ryuusui gave them, and wasted no time reviving him.

Sai Nanami May Be Smarter Than Senku Himself

As his name suggests, he happens to be related to Ryuusui Nanami. In fact, Sai is the older brother of Ryuusui. Ryuusui recalls how, at the mere age of no older than 5, Sai was able to do insanely big calculations all in his head. However, that ended up chaining Sai. The family decided that since he was already a genius, it was best that they taught him only mathematics, so that he could be a great asset.

Sai spent all his time doing nothing but learning mathematics until he started playing video games. Video games were an escape, but soon he started coding video games himself. However, the family didn’t like that, and they took away his video games and made sure that his laptop was only used for learning mathematics.

Sai wanted to code, his family wanted him to do mathematics, and Ryuusui’s solution to that was “Just do both, you’re a genius”. In the flashback, it is shown that Ryuusui was always after his elder brother, always asking him to do some sort of mathematics. Eventually, Sai had had enough, and he ran to India to get enrolled in a computer science program.

Later, on the ship, we saw him writing machine code directly on the walls, as there were no computers available yet. Senku and others asked him what that code was, and he revealed that it was the machine code for the game Dragon Quest. It was clear that all Sai now needs is a computer, and he would become one of the greatest assets of the Science Kingdom.

Dr. Stone Science Future Part 3 Episode 3: Final Verdict

Sai from Dr. Stone | Credit: TMS Entertainment

This episode did not waste any time at all, and the character introduction was done really well. Although introduced late in the narrative, Sai remains a vital character. Furthermore, I love how we now keep getting to see that Senku is not a god. Instead, he is quite realistic when compared to other genius protagonists.

The author didn’t have any reason to add Sai in the story if Senku was going to be actuall all knowing genius; instead, the introduction of Sai shows that he does, in fact, have areas he is not well-versed in. This whole thing adds more layers to the characters and more realism to the story itself.

Anyway, what are your thoughts on this episode? Let us know in the comments.

Dr. Stone Science Future Part 3 is streaming on Crunchyroll.