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Watson S2E20 — The Cobalt Fissure
7.4
Watson•Season 2•Episode 20

The Cobalt Fissure

7.4/10 · 169 votesMay 3, 202644 min

Ranked #16 of 20 in Season 2•−0.1 vs season avg

Discussion

A seemingly random murder outside of UHOP sets the stage for the arrival of someone from Watson and Sherlock Holmes' past.

Directed byLarry Teng
Written bySharon Moalem, Rebecca Hofherr
Previous episodeE19 · Rule of Three
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The Cobalt Fissure

Cast6

Morris Chestnut

Morris Chestnut

Dr. John Watson

Eve Harlow

Eve Harlow

Dr. Ingrid Derian

Peter Mark Kendall

Peter Mark Kendall

Dr. Stephens Croft / Dr. Adam Croft

Inga Schlingmann

Inga Schlingmann

Dr. Sasha Lubbock

Ritchie Coster

Ritchie Coster

Shinwell Johnson

Rochelle Aytes

Rochelle Aytes

Dr. Mary Morstan

Crew3

Larry Teng

Larry Teng

Director

S

Sharon Moalem

Writer

R

Rebecca Hofherr

Writer

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Episode Summary

"The Cobalt Fissure" is episode 20 of Watson season 2. It scored 7.4/10 from 169 votes, ranking #16 of 20 episodes this season (season average 7.5). Directed by Larry Teng and written by Sharon Moalem, Rebecca Hofherr, it aired on May 3, 2026.

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