WARNING: This article contains major spoilers for last week's episode of The Flash, “I Know Who You Are.”


Last week's episode of The Flash finally revealed the that this season's primary antagonist, Savitar, is none other than a future version of Barry Allen. While that naturally raises a range of new questions, it's a twist that Executive Producer Andrew Kreisberg believes is both heartbreaking and exciting.

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"What’s interesting about people’s reactions — we certainly wrote it, but just the way the cast performs it — is it’s one thing to have seen that giant metal suit and hear that there is a version of Barry inside of it," he told Entertainment Weekly. "It’s quite another thing when you actually come face-to-face with what’s inside. Those scenes that are coming up over the next few episodes, as everyone gets a real glimpse of this person, it’s this mixture of both horror and sadness."

Perhaps what makes the revelation of Savitar's true identity such a bitter pill to swallow is that Barry was always a symbol of hope and optimism. Now, as Kreisberg explained, fans have to stomach the difficult truth that the kind, charming hero whose journey they've followed for two and a half years is every bit as corruptible as the criminals he fights.

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"His visage is obviously very upsetting — seeing the scar and the milky white eye, but also seeing the person that you love be so twisted," he said. "Barry Allen, who probably has the gentlest soul of all of the characters in the Arrowverse, to just see how far he could fall, he’s both terrifying, but it’s also heartbreaking."

While it may be heartbreaking for viewers, the twist seems to have added a fun new dynamic to the daily grind for the rest of the cast.

"Watching Jesse L. Martin, Candice Patton, Carlos Valdes," Kreisberg said, "watching all of their reactions and interactions with Savitar when he’s out of the suit, it feels so fresh and exciting for us."

Airing Tuesday at 8 p.m. ET/PT on The CW, The Flash stars Grant Gustin, Candice Patton, Danielle Panabaker, Carlos Valdes, Tom Cavanagh, Jesse L. Martin and Keiynan Lonsdale.