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The Flash S03E20, I Know Who You AreS03E20

The Flash · Season 3

The Flash season 3 episode 20: I Know Who You Are

Aired 2 May 201742 minRated TV-PG

7.8TMDB · 39 votesMark watched

Where to watch The Flash Season 3 in Australia

The Flash season 3 is streaming in Australia on Prime Video (subscription), HBO Max (subscription) and Stan (subscription), and free on 9Now. You can also buy it on Apple TV from $29.99, Fetch TV from $29.99 and Prime Video Store from $27.99.

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Free

Buy or rent

Availability checked 16 November 2026.

What happens in “I Know Who You Are”

Barry and the team meet Tracy Brand, a scientist, who may be the key to stopping Savitar. Unfortunately, Killer Frost is also after Tracy so Team Flash must battle their old friend, which proves to be particularly difficult for Cisco. Joe and Cecile’s relationship takes a big turn.

Episode summary: TMDB.

Before you watch

  • It is episode 20 of 23 of season 3, so watch episodes 1 to 19 first.
  • It runs about 42 minutes.
  • Directed by Hanelle M. Culpepper, written by Joshua V. Gilbert and Bronwen Clark.
  • TMDB users rate it 7.8 out of 10 (39 votes).

The Flash trailer

The official trailer for the series (no preview of this episode has been published).

The Flash trailerPlay video: The Flash trailer

Cast and crew of this episode

Director
Hanelle M. Culpepper
Writers
Joshua V. GilbertBronwen Clark
Guest stars
Danielle Nicolet as Cecile HortonTobin Bell as Savitar (voice) (uncredited)Anne Dudek as Tracy BrandAndre Tricoteux as Savitar

Credits: TMDB.

More from The Flash Season 3

Previous · S03E19The Once and Future Flash25 April 2017Next · S03E21Cause and Effect9 May 2017
  1. E01
  2. E02
  3. E03
  4. E04
  5. E05
  6. E06
  7. E07
  8. E08
  9. E09
  10. E10
  11. E11
  12. E12
  13. E13
  14. E14
  15. E15
  16. E16
  17. E17
  18. E18
  19. E19
  20. E20
  21. E21
  22. E22
  23. E23

Every episode of Season 3The Flash episode guide

Episode names, air dates, runtimes, stills and ratings: TMDB. Air dates are the first broadcast anywhere; where it streams is our daily Australian check.