"Supergirl" star Melissa Benoist isn't sure who -- or what -- is inside the mysterious Kryptonian spaceship revealed in the season finale, but she has some theories.

"I've heard a few rumblings of who it might be," the actress told TVLine at The CW's upfront event.

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Likewise, Benoist isn't sure what the future holds for Kara's relationship with James Olsen, played by Mehcad Brooks. "I have no idea. That is up in the air," she said. "What I love about Kara is about naive and innocent she is about love. Whatever happens, it will be funny and awkward and great."

However, fans can be certain of one thing as production moves from Los Angeles to Vancouver, and "Supergirl" settles into its new home at The CW: crossovers.

Benoit assured that Kara "will be visiting or be visited by a lot of people, not just Barry."

"Supergirl" returns Mondays this fall on The CW.