Credit: Jason Merritt/ Getty Images Photo: Sarah Drew at the 2011 AMAs on November 20, 2011

Taking a page from the world of sci-fi, Grey’s Anatomy explores an alternate universe in an episode scheduled to air next February. As we’ve previously reported, it’s a “What if” episode that has Meredith Grey (Ellen Pompeo) wondering how life would have been different if her mother had never suffered from Alzheimer’s and passed away.

The episode reunites the cast with some familiar faces, among them Kate Burton as Meredith’s mother and Kate Walsh as Addison Montgomery, who in this world is apparently still married to Derek Shepherd (Patrick Dempsey).

But in a world where the genius Ellis Grey is still alive, is Izzie Stevens (Katherine Heigl) still kicking around Seattle Grace? “No,” says Sarah Drew (April Kepner) who just finished shooting the episode. “She’s referred to, but, no, she’s not in it.”

In an exclusive interview with Wetpaint Entertainment, Sarah tells us that her own character, April Kepner, is very much part of this world. “She does something very surprising, which will be fun for the viewers,” she teases.

And life as we have come to know it is upside down.

“It’s the time that we’re in now, but as if everything was different,” she says. “Some people are alive that have died, some people are not there that would have been there. All the relationships are completely different – totally and completely different.”

Apparently it’s an alternate fashion universe as well.

“Everybody’s hair is different, everybody’s look is different. The whole hospital looks different, the scrubs are all different, everything has changed,” Sarah tells us.

The episode gave Sarah a chance to reunite for a couple of scenes with Kate Walsh with whom she got to work in the musical episode, but also, as one of Addison’s very pregnant patients on Private Practice in Season 2.

“I was Dell’s (Chris Lowell) first patient when he became a mid-wife,” she says. “I was this young pregnant girl who was going to give her baby up for adoption and the parents didn’t want the baby because it had health issues. I’ve played pregnant so many times it’s ridiculous. My husband jokes about how many virtual mouths we have to feed.”

But the actress, who in real life is due to give birth in seven weeks, won’t be popping out a baby on Grey’s Anatomy anytime soon – in fact, Sarah tells us there are still no plans for Dr. April Kepner to lose her virginity.

“I keep asking,” she says. “But she’s not getting any action yet!”

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