The Flash Promo: What's Cisco Doing to Barry's Brain?!

Now that he knows the truth about Savitar, Barry's not wasting any time on The Flash Season 3 Episode 21 "Cause and Effect."

Savitar's main advantage has been the fact that he's lived through this battle. He knows every decision, every trick, and every thought his past self experiences.

Thankfully, Cisco's ready, willing, and able to outsmart him.

In the video below, Cisco tells Barry that he's created a way to stop him from remembering things.

Basically, once Barry goes through a minor procedure, he won't be able to hold onto memories. Therefore, Savitar will be left in the dark. Sounds simple enough--in its own, super complicated way.

Unfortunately for Barry, thing don't exactly go the way they'd hoped.

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Press play on the video to see what happens to Barry. Then, hit the comments to tell us what you think.

Will Cisco be able to undo the damage? Has Savitar already seen this coming, too?

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