The Flash: Here's Why Iris' Purple Lightning Matters

Iris (Candice Patton) got the chance to walk a mile (or technically run several miles) in Barry's (Grant Gustin) shoes Tuesday night on The Flash, but you may have noticed one key difference in her and Barry's speedster abilities.

While Barry emits yellow lightning in his wake, Iris trails purple lightning instead. Not only that, she also had a purple speedster suit.

"There's a specific reason we designed the costume the way we did," executive producer Todd Helbing says. "There's a specific reason for the jacket."

Helbing also notes that the choice to make her lightning purple followed along the same lines as the jacket, but it's something we'll have to wait for answers on. At least for now, we can start trying to connect some dots with what we do know about speedster colors and Iris.

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In the history of the show, there's only been one other speedster who left a trail of purple lightning in his wake. When we briefly visited Earth 19 with Gypsy last season, she flipped through photos, one of which was a speedster who zipped away in a flash of purple lightning. Some quick comic research reveals his identity to be Accelerated Man (the Earth 19 equivalent of the Flash), but so far we have no clue as to why certain speedsters emit purple lightning or why that may be important.

We also know from earlier seasons that blue lightning is caused by taking the drug Velocity 6, which also happens to have life-threatening symptoms. Obviously Iris didn't take any drugs when she accidentally got Barry's powers transferred to her and she's trailing purple lightning, so we don't know if these two things could be related at all.

Finally, Iris was able to withstand being in Barry's Flashtime more than any of their other team members. During "Flashtime," almost everyone got a ride on the speedster express but without fail, their bodies started to wear down and they became woozy after barely a minute of moving that quickly. Iris, on the other hand, didn't seem to experience any symptoms either in the courtroom or in her "lighting rod" conversation with Barry when the nuclear bomb went off. Could that be related to what's going on with her and the color she's trailing?

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These could all be completely innocuous tidbits, but if they do manage to fit together somehow, signs point to there being something very special about Iris in regards to how she reacts to the speed force.

The Flash airs Tuesdays at 8/7c on The CW.

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