'The Flash': Mystery Girl's Identity Revealed in Season 4 Finale

Tonight's season finale of The Flash may have been focused on stopping the Enlightenment, but the [...]

Tonight's season finale of The Flash may have been focused on stopping the Enlightenment, but the hit The CW series also just answered the season's biggest question: who is the Mystery Girl?

Major spoilers for tonight's episode of The Flash, "We Are The Flash", below.

The finale saw Team Flash take a serious risk in their efforts to stop Clifford DeVoe/The Thinker (Neil Sandilands) from mind jacking the world with his diabolical Enlightenment satellites and the risk paid off. DeVoe was defeated within his own mind, but the crisis didn't end there. As the Enlightenment fell from the sky, Barry/The Flash (Grant Gustin) raced around trying to stop the falling shrapnel from harming civilians and he soon realized that he wasn't running alone. Another speedster had taken up the cause with him.

That speedster turned out to be the Mystery Girl (Jessica Parker Kennedy) and she had a big bombshell to drop. She wasn't a waitress or a delivery person or even just a friendly person at Jitters buying Ralph (Hartley Sawyer) and Cisco (Carlos Valdes) coffee. No, the Mystery Girl revealed her identity to be that of Nora Allen, Barry and Iris' (Candice Patton) daughter from the future. She'd travelled back in time to because she may have made a very big mistake and needs her family's help.

There were a lot of theories as to who the Mystery Girl would be -- who first appeared during the crossover "Crisis on Earth-X" -- though most fans felt like she would end up being Barry and Iris' daughter. They just didn't quite have the name right. Most fans assumed that the Mystery Girl would end up being Dawn Allen. In comics, Barry and Iris have twins, Dawn and Don Allen (aka the Tornado Twins). Dawn was a natural guess for fans as, in the aftermath of "The Trial of The Flash", Barry runs to the 30th century which is where the twins are conceived.

While Nora is from the future -- which may imply some ties with comics Dawn Allen -- it's not yet clear what her whole story is. What we do know is that her identity was teased in the series premiere, meaning the Mystery Girl's identity was right there the whole time.

During the premiere, Barry's return from the Speed Force left him muttering gibberish and writing strange symbols on any surface he could. One of the things he said, "Nora shouldn't be here", was thought by many to be a reference to Barry's late mother, but now we know that it was, instead, a big hint -- one that only some of us missed.

With the mystery of the Mystery Girl solved, the only thing we want to know now is just how big of a mistake Nora Allen has made..

The Flash will return with new episodes Tuesdays this fall at 8/7c on The CW.