Nestled in the complicated narrative of The Flash is the mysterious and tragic murder of Barry Allen's mother, Nora, which is an event that kicks off a chain reaction that eventually takes Barry through becoming a forensic scientist to try and acquit his dad of his mother's murder and becoming The Flash.

Nora’s life was brutally cut short and the identity of the murderer, a mystery at the heart of The Flash, is never shown in the film, which creates a void waiting to be filled.

However, director Andy Muschietti, in an interview with The Playlist, confirmed that the Reverse-Flash, Eobard Thawne, was the one responsible for Nora's death and would've been revealed had The Flash 2 been greenlit.

The inclusion of the Reverse-Flash in the sequel makes sense when you consider the source material. Thawne's character is crucial in The Flashpoint storyline, which serves as the inspiration for the events of The Flash. 

In the comic books, Thawne kills Nora in cold blood, leading to the alternate reality formed by a heartbroken Barry whose attempts to save her literally formed the basis of an entire comic book storyline that's been revisited several times over the years. But, at the same time, Thawne also embodies a captivating complexity, the type that makes a villain fascinating. He’s an adversary whose hatred for the Flash drives him to unimaginable lengths to destroy everything the Flash stands for. A time traveler from the 25th Century, Thawne's obsession with annihilating the Flash’s legacy is compelling, casting him as a formidable opponent.

Given Thawne's significance, one might wonder why he didn't feature more prominently in The Flash. Perhaps the answer to this question is simple: The Flash was already packed with too many cameos and characters.

Even though The Flash drew from The Flashpoint storyline, it also carved its own path and veered away from becoming a literal adaptation. Balancing multiple multiverse cameos and diverging from the source material, The Flash had much on its plate. As such, it would have been challenging to accommodate the Reverse-Flash adequately. However, this limitation has offered an exciting opportunity for The Flash 2, which could become the perfect canvas for introducing the Reverse Flash to the DC Extended Universe, a move that could catapult the stakes of the sequel.

Unfortunately, this will never happen. The Flash struggled out of the gates at the global box office, getting mixed reviews from audiences and critics alike. Despite getting approval from the likes of Tom Cruise, Stephen King, and even Henry Cavill, as well as an extensive marketing budget, people didn't just want to watch a non-bearing film with the DC Universe set to wipe the slate clean in two years.

If nothing else, the ending to The Flash leaves the door wide open to revisiting its cinematic universe, presumably once the new co-head of DCU Studios has finished building the foundations of the DCU.

For now, though, fans will have to wait for at least a few years to check out what Gunn's brains created with the premiere of Superman Legacy in 2025.

As for Andy Muschietti, The Flash's director apparently did well enough to impress DC Studios to sign him to direct one of the two pillars of the upcoming DCU slate, The Brave and the Bold, which will feature a still-unannounced actor as the Dark Knight.

Despite all of this, the weight of the Reverse Flash's potential involvement in the storyline looms, stirring curiosity and a lot of anticipation among fans. As Muschietti himself admits, “Reverse Flash is the elephant in the room.” But, unless The Flash pulls off a miracle and finds a way to go back in time to find out where everything went wrong for the DCEU (our money's on the firing of Zack Snyder mid-development of The Justice League) and sets its course towards a more profitable future, Eobard Thawne's big-screen debut will have to wait.