Even though The Flash's Barry (Grant Gustin) and Iris (Candice Patton) have been living with the horrifying news that Barry has to die in the Arrowverse's upcoming Crisis on Infinite Earths crossover, the rest of the team are still in the dark. However, they won't stay that way for long, and the fallout of learning their friend is doomed will take its toll on each of them.

"It's a nuclear bomb going off for the team, and specifically for Ralph," Hartley Sawyer told TV Guide of Barry's eventual admission. "That's something that is going to be very challenging for him to take in. It's pretty catastrophic news."

"Barry is like a brother to him," he continued. "Barry is the reason that Ralph is no longer where he was when we met him in Season 4. He got on the straight and narrow because of Barry, so the idea of anything happening to him is catastrophic to Ralph. They have a real bond."

Potentially losing Barry won't be the only family drama Ralph has to deal with though; this week's episode introduces Ralph's mother, who is a bit of a character, as she finds herself in a spot of legal trouble that Ralph and Cecile attempt to help her out of. To say that meeting her is a peek behind the curtain of Ralph Dibny is kind of an understatement.

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"I think it kind of helps fill in the gaps. You see her and you know what you know of Ralph and you're like, 'Oh yeah, that makes sense. That totally makes sense,'" said Sawyer. "I think [he inherited] some of her insecurity and certainly some of the zaniness... But also I think meeting her, it really helped me understand why Ralph has the heart that he has, because he has a very big heart. You see that in her too."

The Flash airs Tuesdays at 8/7c on The CW.

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Hartley Sawyer, The Flash