Did Sasha Alexander REALLY return as Kate?

"Sasha was out of the country at the time and couldn’t come up and play with us. So she very graciously let us use her image, and we recut things into the episode. The sequence in the hospital room, there were hours and hours of opticals that went into that. And we basically took her from a sequence in "SWAK," when they got the plague, and repositioned the colors and re-jiggered and recut. This is what we came up with. I’m very proud of it. It's a challenge to do something like that and I think it worked pretty well."

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