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Dr. STONE S4E31 — Unknown Known

7.8

Dr. STONE•Season 4•Episode 31

Unknown Known

7.8/10 · 680 votesMay 14, 202624 min

Ranked #29 of 37 in Season 4•−0.5 vs season avg

With the computer completed, the team will need a user interface: a TV.

Directed byLin Yingchen

Written byAkira Kindaichi

Previous episodeE30 · Stone to Space Next episodeE32 · Challengers of Science

Seasons4

Season 4 Episodes37

RYUSUI VS. SENKU still

RYUSUI VS. SENKU

SCIENCE JOURNEY still

SCIENCE JOURNEY

Light Trap in the Darkness still

Light Trap in the Darkness

Dr. X still

Dr. X

DOCTOR VS. DOCTOR still

DOCTOR VS. DOCTOR

SCIENCE IS ELEGANT still

SCIENCE IS ELEGANT

The Two Scientists still

The Two Scientists

LOCK ON still

LOCK ON

Light of Science still

Light of Science

Dirty Roads still

Dirty Roads

Those Who Know the Rules; Those Who Make Them still

Those Who Know the Rules; Those Who Make Them

Reunion still

Reunion

Watching the Same Moon still

Watching the Same Moon

EARTH RACE still

EARTH RACE

The Escape still

The Escape

Medusa Mechanism still

Medusa Mechanism

Sickening Yet Beautiful still

Sickening Yet Beautiful

Diamond Heart still

Diamond Heart

Stone Sanctuary still

Stone Sanctuary

What I Once Sought to Destroy still

What I Once Sought to Destroy

Our Dr. Stone still

Our Dr. Stone

Until We Meet Again still

Until We Meet Again

Scientist, All Alone still

Scientist, All Alone

Whole New World still

Whole New World

Future Engine still

Future Engine

Fire still

Fire

The Universe Is Written in the Language of Mathematics still

The Universe Is Written in the Language of Mathematics

Dawn of the Computer still

Dawn of the Computer

The Truth About the Rocket still

The Truth About the Rocket

Stone to Space still

Stone to Space

Unknown Known still

E31 7.8Now viewing

Unknown Known

Challengers of Science still

Challengers of Science

Wanting Everything still

Wanting Everything

Countdown still

Countdown

Giant Step still

Giant Step

Why-Man still

Why-Man

Ushers of an Exhilarating Future still

Ushers of an Exhilarating Future

Cast8

Yusuke Kobayashi

Yusuke Kobayashi

Senku Ishigami (voice)

Makoto Furukawa

Makoto Furukawa

Taiju Oki (voice)

Kana Ichinose

Kana Ichinose

Yuzuriha Ogawa (voice)

Manami Numakura

Manami Numakura

Kohaku (voice)

Gen Sato

Gen Sato

Chrome (voice)

Kengo Kawanishi

Kengo Kawanishi

Asagiri Gen (voice)

Ryota Suzuki

Ryota Suzuki

Nanami Ryuusui (voice)

Karin Takahashi

Karin Takahashi

Suika (Voice)

Crew2

A

Akira Kindaichi

Writer

L

Lin Yingchen

Director

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Episode Summary

"Unknown Known" is episode 31 of Dr. STONE season 4. It scored 7.8/10 from 680 votes, ranking #29 of 37 episodes this season (season average 8.3). Directed by Lin Yingchen and written by Akira Kindaichi, it aired on May 14, 2026.

Next: E32 · Challengers of Science Best of Season 4