Season 4’s greatest mystery on The Flash has finally been revealed in the season finale, confirming that the enigmatic Mystery Girl (Jessica Parker Kennedy) is pretty much exactly who you thought she was. She’s Iris and Barry’s daughter.

Huge spoilers follow for The Flash Season 4 finale “We Are The Flash.”

The Season 4 finale of The Flash aired Tuesday, May 22 and with it came the conclusion to the ongoing conflict against Clifford DeVoe, aka The Thinker, but we also learned that the Mystery Girl was none other than Nora West-Allen — Iris and Barry’s future daughter — all along.

Barry spends most of the episode inside DeVoe’s mind, trying to incept him into becoming a good person again. Yeah, it was always a bad idea, but it works out when Barry finds Ralph in there and is able to get the Elongated Man to regain control over his own body, effectively eliminating DeVoe. But the team still has to deal with a cataclysmic disaster when the S.T.A.R. Labs satellite comes crashing to Earth. It’s a good thing that the Mystery Girl shows up in her speedster suit to help supersonic punch it out of the way with Barry. And that’s just where the fun gets started.

Nora Allen helps Barry punch a satellite.
Nora Allen helps Barry punch a satellite.

Interestingly, after Harry’s intelligence fully deteriorates early in the episode, he began writing the same cryptic runes that the Mystery Girl wrote earlier this season — the same writing that Barry was scribbling when he came out of the Speed Force. Harry also began babbling just like Barry did as well, even saying the exact same words. It was that same language that helped reboot Harry’s brain halfway later on. We still don’t know what the connection here is, but many of the phrases that Barry muttered in the season opener finally get said here.

One of those lines happens in the final minutes of the finale when the Mystery Girl walks right into Cecille’s baby shower wearing Iris’s speedster jacket, promptly announced that she’s Nora Allen, their daughter, and that she’s “made a big mistake.”

In other words, Season 5 is going to be Flashpoint 2.0 because she made the same mistake Barry did by saving her parent from probable death.

Executive producer Todd Helbing admitted last month that we’d finally learn the true identity of the Mystery Girl in the Season 4 finale, and that she would factor into Season 5. All of that proved to be true. Episode 20 confirmed that the Mystery Girl was a speedster after tons of speculation as much, especially considering she could write in the strange Speed Force language. Her being related to Barry in some fashion seemed inevitable, especially considering her lightning is a combination of his and Iris’s speedster colors.

The Mystery Girl first debuted in the “Crisis on Earth-X” crossover event last year and continued to pop up every now and then to tease fans. This is a pretty satisfying confirmation of many fan theories, but there’s still so much more we don’t know about her. Did she selfishly save Barry from dying? Could she have caused an even worse disaster?

It’s too bad we have to wait until Season 5 in October to find out more.