'Grey's Anatomy' Season 12 finale spoilers: Will Meredith-Nathan hookup upset Maggie?

The penultimate episode of Season 12 of medical drama "Grey's Anatomy" saw Meredith hooking up with newbie Nathan.

Meredith has just recently started dating after the death of her husband Derek and her first date was with Will Thorpe, the military doctor. But Meredith ended things when she realised she had developed feelings for the doctor, saying she wasn't ready yet to move on from the death of her husband.

But in Thursday's episode titled "At Last," a frustrated Meredith got into an argument with Nathan that ended with both of them kissing. It remains to be seen if there is a future for Meredith and Nathan, but one thing actress Ellen Pompeo, who plays Meredith, knows is that her character is not yet ready to share the details of her steamy session.

"No one really knows," Pompeo told TVLine. "Maggie has a crush on him, so Meredith can't really reveal what has gone on, because she has to keep it secret from her sister…"

The actress also revealed that she's not sure if the relationship is going to continue. "I think maybe they want to give the fans a little taste and see how they react first, and then they will decide what to do. Shonda is sort of savant in that way. She just gets these ideas, and she's very, very confident about what direction she wants her characters to go in. So maybe she has a plan for next year," Pompeo noted.

Interestingly, fans had predicted a Nathan-Meredith hookup ever since Martin Henderson was cast as Nathan Riggs. This happened shortly after Patrick Dempsey's departure from the show, and many believed Henderson would become the new McDreamy.

"I don't think anyone could ever be the new McDreamy," Henderson told The Hollywood Reporter. "Those are some pretty big shoes to fill. I hope my dynamic with Ellen will be quite different. If they try to make the dynamics of their relationship too similar to what Meredith and Derek had, it's going to feel like rehashing something and that's going to do the audience a disservice."

"Grey's Anatomy" airs Thursdays on ABC.