The Flash (2014– )
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Cause and Effect 

Barry takes desperate measures to stop Savitar, while H.R. keeps pressuring Tracy Brand to set a trap for Savitar and Killer Frost has an interesting proposal.


David McWhirter


Greg Berlanti (developed by), Andrew Kreisberg (developed by) | 5 more credits »




Episode cast overview:
Grant Gustin ... Barry Allen / The Flash / Savitar
Candice Patton ... Iris West
Danielle Panabaker ... Killer Frost
Carlos Valdes ... Cisco Ramon / Vibe
Keiynan Lonsdale ... Wally West / Kid Flash
Tom Cavanagh ... H.R. Wells
Jesse L. Martin ... Joe West
Tom Felton ... Julian Albert
Anne Dudek ... Tracy Brand
Danielle Nicolet ... Cecile Horton
Richard Zeman ... Lucius Coolidge / Heat Monger
Andre Tricoteux ... Savitar
Liam Hughes ... Young Barry
Sasha Rojen ... Young Iris
Ken Camroux-Taylor ... Judge Hankerson


Barry takes desperate measures to stop Savitar, while H.R. keeps pressuring Tracy Brand to set a trap for Savitar and Killer Frost has an interesting proposal.

Plot Summary | Add Synopsis


TV-PG | See all certifications »

Did You Know?


Mick Rory is mentioned at the CCPD as being "off the grid", indicating that the police do not know of his whereabouts. Rory is currently a member of the time-traveling Legends of Tomorrow and not currently in Central City (nor in the year 2017). See more »


While discussing cause and effect with Barry, Savitar mentions how Eobard Thawne is "still kicking around" despite his ancestor Eddie killing himself. Since he's from the future, Savitar should be aware that Eobard was killed by the Black Flash in "DC's Legends of Tomorrow: Aruba" while fighting the Legends of Tomorrow over control of the Spear of Destiny. See more »


Cisco Ramon: So when the Legends found that message in the Waverider from old you saying "Don't trust Barry Allen", it was talking about Savitar Barry Allen.
Cisco Ramon: It's all coming together... in the worst way.
See more »


References Dragon Ball Z (1996) See more »

User Reviews

One of the funniest and most light-hearted episodes in a long time
9 May 2017 | by TrundleTheGr8See all my reviews

For the majority of this episode i was laughing my ass off, just about everything memory-less Barry did was hilarious, i've known for a while that Grant Gustin was an incredibly talented actor but this just sealed the deal. At first when Savitar was revealed i thought i wouldn't be able to take Grant seriously as a villain but he proved otherwise. His actions this episode without his memories really brought me back to the season 1 days, and showed how fun this show can be when it tries not to go all Arrow. Also, I can't get past how amazing Danielle Panabaker looks as Killer Frost, obviously regular Caitlin Snow is beautiful but her as Killer Frost just takes it to a whole other level. I really hope we get to see Frost turned back to normal or to see Killer Frost herself turned to a hero or at the least an anti-hero. I know it wouldn't be comic accurate but after all these seasons I really want Caitlin to be a part of team flash rather it be her regular self or Frost. Either way this episode seriously brought me back to the good ol' days of this show and it was such a great feeling.

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Release Date:

9 May 2017 (USA) See more »

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Sound Mix:




Aspect Ratio:

16:9 HD
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