All year long The Flash has seen Cisco rocking his Vibe costume (even giving Barry a future upgrade), so where are Caitlin’s Frost-y new threads? Watch Killer Frost make her formal Earth-1 debut in new Savitar-teasing photos and footage of next week’s “I Know Who You Are.”

Spoilers for those not yet caught up on The Flash Season 3, but now that a Killer Frost-ed Caitlin has officially signed on to Team Savitar, our first photos from Tuesday’s “I Know Who You Are” finally introduce the blue-and-silver costume teased in earlier featurettes (which … I guess Savitar made?). Star Danielle Panabaker even spoke to TVLine of the outfit tweak from Earth-2’s Killer Frost, saying:

In the research that I did about Killer Frost, she always wore boots, which was something that I was really pulling for … And I know some of our producers really loved this long cape version [of the character], which is great and feels very villainous. I love the sleeves on it because a lot of Killer Frost’s action is with her hands, and hopefully the light will really catch all the different details on that.

Following this past Tuesday’s tease of Savitar’s identity, “I Know Who You Are” will also introduce Anne Dudek’s Tracy Brand, seen in the photos above and synopsis below:

VIBE FACES OFF AGAINST KILLER FROST — Barry (Grant Gustin) and the team meet Tracy Brand (guest star Anne Dudek), a scientist, who may be the key to stopping Savitar. Unfortunately, Killer Frost (Danielle Panabaker) is also after Tracy so Team Flash must battle their old friend, which proves to be particularly difficult for Cisco (Carlos Valdes). Joe (Jesse L. Martin) and Cecile’s (guest star Danielle Nicolet) relationship takes a big turn.

It’s all building toward the May 23 finale, so check out the extended trailer for “I Know Who You Are” below, and stay tuned.

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