Uploaded May 2017 | Updated September 2026, 2 weeks ago

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The Flash - Episode 3x21: Cause and Effect Promo #2 (HD)

Barry (Grant Gustin) takes drastic measures to stop Savitar. Meanwhile, H.R. (Tom Cavanagh) continues to push Tracy Brand (guest star Anne Dudek) to design the trap for Savitar and Killer Frost (Danielle Panabaker) returns with an interesting proposal. David McWhirter directed the episode written by Judalina Neira & Lauren Certo (FLA321). Original airdate 5/9/2017.

The Flash 3x21 Extended Promo/Preview "Cause and Effect"
The Flash Season 3 Episode 21 Extended Promo
The Flash 3x21 Extended Promo "Cause and Effect" (HD)

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