The Flash Finale Finally Makes Good on a Long Held Fan Theory

On Wednesday night, bringing together several plot points and storylines as the Arrowverse series wrapped up Barry Allen’s story. Among the elements that the series finale included was the delivery of a long-held fan theory about one of The Flash’s most interesting foes from comics — but with a very The Flash twist.

Warning: spoilers for The Flash series finale, “A New World, Part Four” beyond this point.

In last week’s penultimate series episode, Eddie Thawne (Rick Cosnett) returned to life in 2049, but is soon tempted by the Negative Speed Force with its mysterious blue crystal, telling him that Barry Allen (Grant Gustin) isn’t his friend or his ally, but that Barry took the life he should have had and his Season 1 sacrifice had meant nothing. The episode ended with Eddie being lured by the crystal, but we didn’t see him fully embrace it. That changes in the series finale. At the West house — or rather the Negative Speed Force manifestation of it, not only does Eddie assemble Godpseed, Reverse-Thawne, Savitar, and Zoom, but he embraces the crystal and becomes the avatar for the Negative Speed Force and calls himself Cobalt Blue, complete with a comics accurate costume.

“Rick is another one that blew me away,” Gustin said “of Cosnett’s appearance previously. “I mean, we had some really cool scenes the last couple episodes and he kind of ran the gambit with his performance in the last few. I mean, he got to do some really interesting stuff. There was some really fun stuff for him. It’s unlike anything he’s done on our show before and I think based off conversations I had with him it was unlike anything he’s done in his career. I mean, he really got to do a lot of fun stuff in the last couple episodes and he really impressed me.”

Eddie’s transformation into Cobalt Blue delivers on something that fans have been hoping to see since the series began, though it does so with a bit of a twist. In comics, Cobalt Blue is Malcolm Thawne — Barry Allen’s secret twin brother who was stolen from the Allens at birth and given to the Thawnes. On The Flash, Eddie isn’t Barry’s secret twin — he really is just Eddie Thawne — but his motivation for hating Barry is the same (though Eddie’s is also manipulated by the Negative Speed Force): he feels like Barry took the life he should have had.

However, while The Flash finally giving fans the arrival of Cobalt Blue in what is the final battle for Barry Allen does deliver on that fan theory and fan desire, it’s a little bittersweet about its timing. With it coming in the series finale, Cobalt Blue’s time on The Flash is short-lived. Barry ultimately is able to come to a truce of sorts with Eddie, convincing him to remain the avatar of the Negative Speed Force so that they can coexist, but not to give into its anger, thus saving reality itself.

What did you think about The Flash finally delivering Cobalt Blue? What did you think about The Flash series finale over all? Let us know your thoughts in the comment section.