Season 11 of Grey's Anatomy has yanked at MerDer heartstrings repeatedly since there was the whole cheating storyline involving Dr. Derek Shepherd (Patrick Dempsey) and one of his fellows in Washington, D.C.

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Plus, it seemed like he resented Dr. Meredith Grey (Ellen Pompeo) at the beginning of the season since she was keeping him from his D.C. dreams, but he obviously ended up there and is now back, but something is up.

During the episode that aired Thursday, April 9, called Crazy Love, it ended in a strange way. Meredith received a phone call from the White House inquiring where Derek is since he never showed up for his meeting. Nobody has heard from him since he left and Meredith doesn't panic and kind of just shrugs it off thinking his flight got delayed.

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She even scribbled his name with a question mark on a notepad.

It turns out Derek's whereabouts are crucial though and of great concern. In the promo teaser below for next week's episode called One Flight Down, Meredith is seen calling Derek and getting his voicemail. Plus, she has a concerned look on her face as if she knows something is off about him missing his meeting and not getting in touch with her or anyone else.

In the promo, Meredith confides in Dr. Miranda Bailey (Chandra Wilson) about her concerns over Derek's whereabouts.

"At 5 p.m. if you haven't heard from him you can panic," Bailey tells her.

Dr. Maggie Pierce (Kelly McCreary) also picks up on Meredith's concerns and says to her, "You're freaking out, aren't you?"

Grey's Anatomy airs on Thursday nights at 8 p.m. ET on ABC.

Tags: greys anatomy ABC television