What Do We Know About ‘The Flash’s’ Mystery Girl After Last Night’s Reveal?

I’m going to be honest with you, I haven’t been a huge fan of The Thinker as a villain on CW’s The Flash this season. Clifford DeVoe has been a pretty boring villain and he doesn’t have the sort of emotional resonance as Reverse Flash had in season one or Deathstroke had on Arrow’s second season. DeVoe is basically the Kanye West of Arrowverse villains; he’s convinced he’s smarter than everyone else, that he’s the only person who sees the real truth, and he’s come to the dumbest possible conclusion from that. Even killing fan-favorite supporting character Ralph Dibney and living inside his body wasn’t enough to make DeVoe feel like a villain on the same level as Eobard Thawne who was as smart, if not smarter than DeVoe, and had super speed and a serious emotional connection with Team Flash.

So while last night’s episode was all about DeVoe’s backstory (spoiler: he was a jerk who treated his wife like crap even before the particle accelerator explosion), the only part of the episode that ended up being that compelling was another visit from the Mystery Girl, who first showed up at Barry and Iris’s wedding during the Crisis on Earth-X crossover. This time, Mystery Girl, played by Jessica Parker Kennedy, showed up at Cecile’s baby shower with a gift and accidentally blurted out the day Joe and Cecile’s baby would be born, which just happens to be the day the season finale is going to air.

But then something happened when Mystery Girl saw Iris West-Allen. She bolted before Iris could see her. And by bolted, I mean she ran off using super speed that left purple and yellow lightning in her wake.

This has lead to a lot of speculation that she’s either Iris and Barry’s daughter or Joe and Cecile’s daughter, the later presumably because who knows anyone’s birthday but their own offhand?

Here’s what we’ve seen of Mystery Girl so far. In her first appearance, she was at Barry and Iris’s wedding as a caterer who had a brief scene with Barry where she seemed just a little too enthusiastic to see two random strangers get married. When we next see her, she buys Ralph and Cisco coffee and rambles for a full minute about karma and helping people, before she sits and writes in a journal using the same strange symbols Barry was writing with when he emerged from the Speed Force in the season premiere. She shows up again at CC Jitters to bump into Harry and Caitlin, who she only talks to for a second but she was apparently there to meet them.

In that same episode, “Enter Flashtime,” Jay Garrick, the Flash of Earth Three, mentions he’s mentoring his replacement, who he mentions is a girl. I’m pretty sure that wasn’t an offhanded line either, it seems pretty obvious that Mystery Girl is being trained by Jay to become the next Flash of Earth Three. But who is she?

The most accepted theory on social media is that she’s Dawn Allen, Barry and Iris’s daughter. I’m not entirely convinced, because Dawn Allen has a twin brother who has been nowhere to be seen. And Mystery Girl seems to have knowledge of future events, which points to her being a time traveler.

There is a character in the Flash mythos from the future with super speed and a ponytail who leaves a purple and yellow streak behind he when she runs, but it’s not Dawn Allen, it’s her daughter, Barry’s granddaughter, Jenny Ognats, also known as XS.

.@TalkingTheFlash @CW_TheFlash Accelerated Man is great and all but when are we going to see XS? @TheCWSupergirl or @TheCW_Legends #TheFlash pic.twitter.com/d2nGIdUnKc

— Alex Hernandez (@alexthoth) December 3, 2016

And that language she and Barry were writing in? It isn’t Interlac, the language used by The Legion of Super-Heroes (who have had a season-long arc on Supergirl this year) in XS’s timeline, but it shares some similarities with that language. Probably enough that it could be a changed version of Interlac to avoid spoiling the reveal in the season premiere. I’m putting my money on Mystery Girl being XS, or at least some combination of XS and Dawn Allen into a single character, the way Mia Dearden became Oliver’s sister Thea Dearden Queen on Arrow.

Whoever she is, Todd Helbing told EW that we’d find out her identity in the season finale, and that she’s been showing up to foreshadow the plot of season five.