'The Flash': 5 things to remember before Season 4

Adam Lance Garcia
Producer, Yahoo Entertainment

The Flash is racing back to your TV tonight, and after a season filled with time travel, parallel universes, and evil-future-time-remnants, it might be hard to wrap your head around all these chronologically confusing paradoxes.

Honestly, we’re surprised we made it through that sentence.

To help clear things up before tonight’s Season 4 premiere, here are the major plot points you’ll need to remember from a linear, subjective point of view:

With the entire third season leading to the death of Iris West (Candice Patton) at the hands of Barry Allen’s (Grant Gustin) evil doppelgänger, Savitar, we were shocked to discover that H.R. (Tom Cavanagh) had taken Iris’s place, sacrificing himself with the help of a facial transmogrification device.

When his plans to create his own existence (via a bootstrap paradox) failed, Savitar tried to unleash himself into every moment in time. But with the help of Jay Garrick (John Wesley Shipp), the Flash was finally able to defeat his mad time-remnant.

With Savitar bested, Caitlin Snow (Danielle Panabaker) was able to break free of her Killer Frost alter ego. But don’t expect her to return to S.T.A.R. Labs any time soon. She’s neither Caitlin nor Killer Frost. “I’m something else,” she said, reading from Stephen Amell’s voice-over script. “And I need to figure out what that is.”

But after Jay Garrick was freed from the Speed Force prison, reality began to grow unstable. With Central City close to cataclysm, Barry offered himself in Garrick’s place to save Central City — and disappeared into the vortex.

Will Team Flash rescue Barry from the Speed Force? We’ll find out tonight.

The Flash Season 4 premieres Oct. 10 at 8 p.m. on the CW.

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