Warning: This article contains spoilers for the Season 4 finale of The Flash, titled “We Are The Flash.”
The Flash ended its fourth season by answering one of the biggest mysteries in the series: Who is Mystery Girl, the strange woman who’s been quietly popping in and out of Barry’s life all season? “We Are the Flash” revealed that the prevailing fan theory is correct. Mystery Girl is Barry and Iris’ daughter from a future timeline. Basically, the series has introduced its version of Dawn Allen from the comics, though in this incarnation she’s named Nora West-Allen instead.