ABC's longest running medical drama Grey’s Anatomy will return with its 21st season on Thursday, 26 September. 

Hints were dropped from this week’s teaser as to Debbie Allen’s (Catherine Fox) plan to overhaul the hospital after the inner turmoil among Grey Sloan Memorial Hospital staff in Season 20 has ramped up. 

In the previous season’s dramatic turn of events, Miranda Bailey (Chandra Wilson) put herself on edge with Allen to protect her interns, and the new season’s sneak peek shows Bailey is just about to begin when she slaps Allen in the face who spits “just another doctor” remark on her. 

As Allen continues to spite her staff after Meredith Grey’s (Ellen Pompeo) decision to resign to pursue her Alzheimer's research, Chief of Surgery Teddy (Kim Raver) is sidelined after agreeing to fund the secret research trial.

Meanwhile, A Million Things actress Floriana Lima will be joining the series in a recurring role and will play Nora, Owen Hunt (Kevin McKidd) and Megan Hunt’s childhood friend (Abigail Spencer). Nora’s character will first appear on 3 October, during the second episode of the season. 

The show also announced the return of some characters, including Dr. Sydney Herron, played by Kali Rocha. 

Viewers have the option to stream Season 21 episodes on Hulu, while the first 20 seasons are available on Netflix.