Houston, we have a problem -- a big one. According to reports, episode 20 of “Grey’s Anatomy” Season 11 will feel like déjà vu as our favorite Grey Sloan doctors come face-to-face with a disaster they’ve previously experienced first hand: a plane crash.

“A small plane crash in Seattle causes multiple casualties,” the summary for “One Flight Down” reveals, adding that the accident will bring back “horrible memories to the doctors, especially Meredith (Ellen Pompeo) and Arizona (Jessica Capshaw).”

As dedicated fans of the hit ABC series will remember, Meredith and Arizona (along with Lexie [Chyler Leigh], Cristina [Sandra Oh], Derek [Patrick Dempsey] and Mark [Eric Dane]) were just a few of the doctors from Seattle Grace that were aboard a plane that crashed into the woods in Season 8. Some of doctors suffered fatal injuries like Lexie, who was crushed by a piece of the plane, and Mark, who suffered internal damage that eventually led to his demise.

Although Mer was only scratched up in the crash, she was forced to watch the death of her sister and witness the graphic scene of her husband’s mangled hand, which had gotten stuck in the wall of the plane. Arizona suffered even worse trauma as her leg was gruesomely injured in the crash, causing her bone to break out. Due to infection, Arizona's leg had to be amputated.

Mer and Arizona will spend episode 20 in a dark place -- literally -- as they hide out in the supplies closet while victims are rushed into the ER.

“There’s got to be some rule people who have been in a place crash can’t work on one,” Alex (Justin Chambers) says in a promo video for the installment. From the remainder of the trailer, it looks as though the two doctors will suffer from PTSD, leaving them unable to lend a helping hand during the incident.

“Dr. Grey, do you need to be replaced?” Bailey (Chandra Wilson) calmly asks Mer, who is coming apart at the seams. And we can’t blame her -- not only does she have to relive a horrific moment from her past, but her husband is also missing.

In episode 19, Meredith received a phone call questioning Derek’s whereabouts. Apparently he never arrived to his meeting in Washington. (Seriously, just when their relationship starts to get back on track Dr. McDreamy has to go missing!) The only fear we have is that Derek might have been aboard the plane that came tumbling out of the sky.

“If at 5 p.m. you haven’t heard from him, you can panic,” Bailey tells her stressed-out co-worker in the promo video for episode 20.

Meanwhile, Owen (Kevin McKidd) and Amelia’s (Caterina Scorsone) breakup will make for an “uncomfortable working situation for Stephanie (Jerrika Hinton),” the synopsis for next week’s episode concludes. (Who thinks these two should call it quits?)

What do you think will happen in episode 20 of “Grey’s Anatomy”? Where do you think Derek is? Sound off in the comments section below with your theories and don’t forget to tune in to episode 20 of “Grey’s Anatomy” on Thursday, April 16, at 8 p.m. EDT on ABC.