"Supergirl" star Melissa Benoist has opened up about her initial doubts that the crossover with "The Flash," "Worlds Finest," would ever happen, due to the complications of sharing the properties between networks CBS and The CW.

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"I honestly didn't think it was possible between networks." Benoist told Variety in an interview. "I remember [executive producer] Andrew Kreisberg telling me right before Grant [Gustin] and I presented at the Golden Globes, 'we're gonna just pitch the idea and see how they respond,' and I remember thinking, 'oh my god, this is going to happen. It has to! There's no way in the world that people wouldn't see how valuable that could be and how awesome it could be and how much the fans would love it.'"

Touching on the prospect of more "Supergirl" crossovers with other Arrowverse characters, "Flash" star Grant Gustin said, "That would be so ideal, and I think that's the goal, but I do not make those decisions - I just hope it happens."

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"Supergirl" and "Flash" executive producer Andrew Kreisberg added, "We never want to say never to anything...I think if it's successful and it works well and there's an audience for it and people are excited by the prospect, we're always game."

"Worlds Finest" airs Monday, March 28 at 8/7c on CBS.