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Dr. Stone Wiki

The Culmination of Two Million Years (200万年の結晶 Ni-hyaku-man-nen no Kesshō) is the fifteenth episode of the Dr. Stone anime.


With Magma defeated, it's down to Senku and Ginro to take the throne. Although both are on the same team, personal greed and opportunism drive one. The fight is on!

Plot Details[]

Senku beats Ginro

Senku beats Ginro.

Ginro tells Ruri that Senku and he will forfeit their fight and Chrome will be the winner, just as she would prefer. However, being in that position, Ruri states she would marry the winner, no matter who he is. Ginro misunderstands it, thinking she has no preference. As the second semifinal between him and Senku starts, Ginro takes Senku seriously, as he had imagined himself as the village chief, and quickly turns the crowd against him with his fantasies. Chrome throws Suika's mask at Senku. Seeing that, Ginro decides to act quickly before he uses some crazy sorcery; however, Senku uses the mask as leverage and smacks Ginro in the balls, knocking him out and taking the victory.

Senku obtains alcohol

Alcohol obtained!

Next are the finals, and Senku intends to lose on purpose so that Chrome can marry Ruri. However, Chrome is unconscious and unable to fight. Everyone is shocked, but having no choice, they announce Senku as the winner and the man who will marry Ruri and become the village chief. Senku agrees to do it and asks them to bring the wine. Ruri coughs up blood, and Senku realizes they are out of time. He wants to make antibiotics, but the villagers explain that he first needs to celebrate all night. Hearing that, Senku then announces his divorce, takes the alcohol with him, and heads to make the medicine.

Ruri takes the medicine

Ruri takes the medicine.

Returning to their base, Senku leaves Kaseki and Gen Asagiri watch over a spinning bamboo at a waterfall. At their base, as a first step, Senku takes burned coal and washes it with hydrochloric acid, then adds ethyl acetate made from alcohol and vinegar to get anillin. They proceed to do 25 more steps. In the morning, Gen is eager to see what is inside the bamboo and is surprised by its carbonated water. Happy that Senku may indeed be making cola, he returns to their base to find Senku and the rest lying on the ground, as the experiment went wrong. Senku explains how he mixed some things, and it caused a small explosion. Taking the carbonated water, Senku mixes it with sodium hydroxide and creates baking soda. After mixing the last ingredients, after six months of arduous work, Senku created the sulfa drug.

Ruri makes complete recovery

Ruri makes complete recovery.

The group heads into the village, but as Gen isn't allowed, he must stay out. Senku tells him to stay and wait for them in the lab. Gen is disappointed; he can't see Ruri getting better, but upon entering the lab, he sees a bottle of Senku's cola on the table and happily drinks it. Senku's group meets with Ruri, and he gives her the medicine. As he examines her, he sees a dead mouse and takes it back to his lab. Making an autopsy, Senku confirms the mouse also has a bacterial infection and explains that depending on the bacteria, his cure may not work. Moments later, Suika calls them as Ruri gets worse. Seeing Ruri's condition getting worse, Senku admits it may be due to his medicine and explains that the bacteria is getting serious and is making allies by spreading its toxic genes into the harmless bacteria around it. That is the pneumococcus bacteria's special move, making him realize Ruri has pneumonia, but his medicine destroys the pneumococcus bacteria. If they keep giving her the medicine, she will recover. With everyone's support, Kokuyo and the rest accept. Soon, Ruri makes a complete recovery. Kokuyo announces Senku as the village chief of Ishigami Village. Hearing Ishigami's name surprises Senku, and Ruri tells him she is aware his name is Senku Ishigami.







  • Ishigami Village
  • Kingdom of Science
  • A small waterfall by the river

Inventions and Discoveries[]

  • Water carbonating machine
    • Carbonated water
  • Various intermediate chemicals of the sulfa drug process
    • Ethyl acetate
    • Anillin
    • Glacial acetic acid
    • Ketene
    • Acetic anhydride
    • Acetanilide
    • P-acetamidobenzenesulfonyl chloride
    • P-acetamidobenzenesulfonic acid
    • Sodium bicarbonate
      • Sulfanilamide antibiotics
  • Senku Cola
  • Stethoscope (makeshift, using a beaker as such)
  • Autopsy (of a mouse)
    • Scalpel and face mask

Anime to Manga Differences[]

  • In the manga, Suika comments that Senku is not a devil for allowing Chrome to rest after the Grand Bout. In the anime, she says nothing.
  • A scene was extended within the events of Chapter 41 which heavily implied that Ruri told Kokuyo to make Senku the next village chief. In the manga, it seemed like it was Kokuyo's idea, though it was not specified.



Site Navigation[]

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Story Arcs
Prologue Saga
Stone Formula Arc
Chapters 1234
Episodes 12
Vs. Tsukasa Arc
Chapters 56789101112
Episodes 345
Ishigami Village Saga
Kingdom of Science Arc
Chapters 131415161718192021222324252627282930313233
Episodes 5678910111213
Village Games Arc
Chapters 34353637383940
Episodes 131415
Village Origins Arc
Chapters 4142434445
Episodes 1617
Stone Wars Saga
Vs. Hyoga Arc
Chapters 4647484950
Episodes 1819
Communications Arc
Chapters 5152535455565758596061626364656667686970717273747576777879808182
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Source of the Petrification Saga
Age of Exploration Arc
Chapters 8384858687888990919293949596979899 100
Episodes 35Ryusui3637383940
Treasure Island Arc
Chapters 101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138
Episodes 4142434445464748495051525354
The Truth of the Petrification Saga
New America City Arc
Chapters 139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169
Episodes 555657
South America Arc
Chapters 170171172173174175176177178179180181182183184185186187188189190191192193
New Stone World Arc
Chapters 194195196197198199200
Globetrotting Arc
Chapters 201202203204205206207208209210211212
Stone to Space Saga
Moon Mission Arc
Chapters 213214215216217218219220221222223224225226227228229230231232