"Grey's Anatomy" spoilers tease tense moments are ahead for Owen (Kevin McKidd), Nathan Riggs (Martin Henderson), Megan (unknown), Meredith (Ellen Pompeo), and Amelia (Caterina Scorsone) during Season 14. Megan's arrival will cause chaos as a massive showdown between Owen and Riggs is brewing.

Nathan cannot believe Megan's alive

"Grey's Anatomy" spoilers reveal that Nathan was shocked to find out that his former fiancee, Megan didn't die ---she's alive. Even more shocking because she has been away for nearly a decade. Meredith told Riggs to go to her and admitted that she felt jealous.

She would love to get a call that Derek (Patrick Dempsy) was alive. Little does Mere know, Owen will probably prevent Nathan from seeing his sister.

"Grey's Anatomy" showrunner, Shonda Rhimes revealed that the fans shouldn't assume that Nathan and Meredith are over. They have a great relationship and are friends as well as lovers. It will be very hard for Nathan to shut the door on his relationship with Meredith, even if Megan wants to resume their relationship.

Megan has been gone for ten years, which is a very long time.

Even if Owen allows his sister to see Riggs, their time is probably over, especially considering Nathan cheated on her which is why she was on the helicopter, to begin with.

Megan's arrival spooks Owen

There is only one word to describe Owen's demeanor ---shocked. He believed his sister was dead and all along, only to learn that she was alive.

Of course, this revelation will probably make both him and Riggs feel awful, knowing that she was alive and alone.

The main question "Grey's Anatomy" needs to answer is where Megan has been for the past decade. Does she remember her life before or will she not remember any of her loved ones?

All eyes on Megan

The spoilers suggest that all eyes will be on Megan as the fans wait to find out if she remembers Owen and Riggs.

Owen is nervous about seeing his sister for the first, anxious about what type of medical care she may need. Riggs has a serious case of anxiety, as well. He isn't sure what Megan remembers about their last encounter. He knows he loves her, but how does she feel about him. It's been ten long years, after all.

"Grey's Anatomy" fans, will Megan's arrival set the wheels in motion for Amelia and Owen to get back together? Will Megan even want to be with Riggs? How will Meredith deal with losing Nathan?

"Grey's Anatomy" Season 14 returns to ABC in September