WARNING: The following article contains spoilers for Season 1, Episode 3 of Dr. Stone, "Weapons of Science."
Having made a major blunder in the previous episode with their first revival choice, Tsukasa -- which was, admittedly, made under the extreme pressure of a surprise lion attack -- Senku and Taiju use their special formula to bring back their original choice: Yuzuriha, the love of Taiju's young life.
After 3,700 years of being encased in stone, like the rest of the human race, Yuzuriha acclimatizes to her bizarre new environment quickly, pledging to assist her liberators in putting up a united front against their newly-made enemy, Tsukasa. The abnormally strong "primate high schooler" was a key ally to Senku and Taiju after they revived him, but it didn't take long for his true colors to show.
Embittered by a bad childhood experience with a selfish, alcoholic older man, Tsukasa took issue with Senku's goal to bring back everyone on Earth. Instead, the hunter believes that the event that created the Stone World should be treated as a chance to create a new one inhabited only by the young and idealistic.
Episode 3 sees Tsukasa continue his ageist rampage -- shattering the stone bodies of whoever he deems unworthy of revival to prevent Senku from carrying out his plan. He rationalizes his actions as a "cull" rather than a murder spree. The tension growing between him and Senku's group comes to a head after Yuzuriha is brought back. She and Taiju ignore the scientist's suggestion that the two of them escape, leading to them becoming targets when he attacks their camp.
As Taiju valiantly uses his body as a human shield against Tsukasa's assault, giving Senku time to load up a little something he cooked up earlier -- a crossbow. Unfortunately, Tsukasa demonstrates his inhuman reflexes by catching the flint bolt before it can pierce him, and the group is forced to flee.
Or at least, make it look like they're fleeing. Senku, frustrated at the constraints of their primal world, realizes they need to fasttrack the modernization process in order to build something that the powerful teenager can't so easily snatch from the air. If they don't, it's only a matter of time before he figures out how to engineer the revival formula for himself, enact his "cull" on a larger scale and kill anyone who stands in his way. By turning tail, he hopes to throw Tsukasa off of their scent, while leading Taiju and Yuzuriha somewhere he hopes will give them what they desperately need.
Their six-hour journey is a hard one to navigate unaided by maps or recognizable landmarks, but following Yuzuriha's hazy memories of the area, the trio comes across a giant bronze Buddha statue. For the freshly-revived girl, it's an emotional find -- reminding her that the land she now finds herself in isn't so foreign after all. It was once her home, and it still can be. It also serves as a much-needed marker that they're heading the right direction.
As Senku reminds us, bronze is immune to being eroded, which is why the Buddha still stands thousands of years after it was built. More importantly, he can harvest the metal to improve their current living situation -- drawing accusations of "blasphemy!" from Taiju. It seems like the arrival of a new Bronze Age is on the horizon, however, that's not all.
When they finally reach the end of their journey, Senku reveals why he led them there. At the foot of a volcano, Japan's famous hot springs are still bubbling away. Where there are hot springs, Senku points out, there's sulfur -- a key ingredient in gunpowder.
That's right: Senku is planning on making guns. Didn't that escalate quickly?
New episodes of Dr. Stone air every Saturday night as part of Cartoon Network's Toonami block, and every Friday on Crunchyroll.