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The Flash S05E08, What's Past Is PrologueS05E08

The Flash · Season 5

The Flash season 5 episode 8: What's Past Is Prologue

Aired 4 December 201842 minRated TV-PG

8.1TMDB · 30 votesMark watched

Where to watch The Flash Season 5 in Australia

The Flash season 5 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 $7.99, Fetch TV from $44.99 and Prime Video Store from $29.99.

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Free

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Availability checked 16 November 2026.

What happens in “What's Past Is Prologue”

Barry and Team Flash come up with a plan to stop Cicada. However, the plan calls for Barry and Nora to travel back in time to gather some key necessities. However, Barry hesitates, concerned about his daughter seeing certain parts of his life. Meanwhile, Sherloque takes his concerns about Nora to Iris, and Caitlin turns up a key asset in the fight against Cicada.

Episode summary: TMDB.

Before you watch

  • It is episode 8 of 22 of season 5, so watch episodes 1 to 7 first.
  • It runs about 42 minutes.
  • Directed by Tom Cavanagh, written by Todd Helbing and Lauren Certo.
  • TMDB users rate it 8.1 out of 10 (30 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
Tom Cavanagh
Writers
Todd HelbingLauren Certo
Guest stars
Tony Todd as Zoom (voice)LaMonica Garrett as Mar Novu / The MonitorJohn Wesley Shipp as Henry AllenBenita Ha as Paramedic #1Troy Rudolph as Paramedic #2Chad Rook as Clyde MardonIslie Hirvonen as Grace GibbonsLossen Chambers as Dr. Vanessa Ambres

Credits: TMDB.

More from The Flash Season 5

Previous · S05E07O Come, All Ye Thankful27 November 2018Next · S05E09Elseworlds (I)9 December 2018
  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

Every episode of Season 5The 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.