The Flash: The Race Is on to Save Iris in "Success Is Assured" Preview

The CW has released the official synopsis for the sixth season finale of The Flash, "Success Is Assured". The episode was originally intended to be the end of what showrunner Eric Wallace referred to as the second act of the series' second "graphic novel" of Season 6 but due to the coronavirus pandemic is now doing the heavy lifting as the series' season finale and, from the looks of things, will have no shortage of tense moments and mystery leading up into those final moments.

Those tense moments appear to center largely around Iris' (Candice Patton) condition in the Mirrorverse. As we've seen first in Eva McCulloch's (Efrat Dor) and more recently with Iris, the Mirrorverse messes with people. In tonight's episode in particular, Iris was struggling with the neural dissonance issue, making it difficult for her to think clearly and even had physical impact as well. The preview for "Success Is Assured" makes it clear that the clock is ticking on rescuing Iris and the others from the Mirrorverse, but fans may not want to get too excited about the prospects of major resolution to the story.

Gustin recently told ET that because things shifted due to the pandemic, not everything will be tied in a neat little bow and that while things with Iris come to a head in episode 6x19 -- the new season finale set to air next week -- things won't be resolved quite the way fans might like.

"Yeah, there's definitely no bow this year," Gustin said. "Generally, we tend to finish the season with a little bit of, you know, we like that element [of surprise] to end the year and to keep everybody waiting during the hiatus time -- but a lot more than usual is left unfinished. It's not necessarily a reconciliation with a lot of things that were going on with Team Flash, and Barry and Iris' separation and the mirror-verse -- so yeah, there's a lot that is left unfinished. As we saw in the last episode, Barry had started to catch on in 617 and he finally was having this epiphany that he hadn't been living with his wife, and something was going on. He shares his concerns with Cecile and the team starts to catch on to what's been happening and that maybe Iris is somewhere else. We'll see that start to develop a little bit more in 618 and things will definitely still come to a head in 619, but it doesn't get resolved as much as we'd probably like it to."

You can check out the official episode synopsis for the episode below.

"THE FLASH" SEASON FINALE – Barry (Grant Gustin) considers a risky plan to save Iris (Candice Patton) from the Mirrorverse. Ralph (Hartley Sawyer) attempts to stop Sue (guest star Natalie Dreyfuss) from making a grave mistake that could destroy her life. Phil Chipera directed the episode written by Kelly Wheeler & Lauren Barnett."

The Flash airs on Tuesday nights at 8 p.m. ET/PT on The CW, before episodes of DC's Legends of Tomorrow. "Success is Assured" will debut on May 12.