<P> The season, garnered 11.21 million average viewers and was ranked 21st overall in total viewers which is fifteen spots higher than the previous season . TV critics and analysts noted the renewed interest in viewership with Rich Kissell of Variety calling it a' renaissance .' Grey's Anatomy finished the 2015--16 television season as ABC's highest - rated drama in the 18 - 49 demographics and also ranked among the top five dramas on all of broadcast, averaging a 3.9 rating in the demo, an unprecedented accomplishment for a show in its 12th season . On March 3, 2016, the network renewed Grey's Anatomy for a thirteenth season . </P> <P> The season follows the story of surgical residents, fellows, and attendings as they experience the difficulties of the competitive careers they have chosen . It is set in the surgical wing of the fictional Grey Sloan Memorial Hospital, located in Seattle, Washington . </P> <P> The season takes place three months after the events of the last season finale in which Richard and Catherine got married . April and Jackson's relationship has hit the rocks after April has resumed her work overseas in Jordan, leaving Jackson high and dry once again . Once the new intern year begins, Meredith Grey (Ellen Pompeo) starts teaching the new interns an anatomy class . Miranda Bailey (Chandra Wilson) is appointed the new Chief of Surgery, much to the dismay of her husband Ben Warren (Jason George), who starts to feel like he is the inferior one in their relationship, leading to some tension between the two . </P> <P> Maggie Pierce (Kelly McCreary) begins a relationship with intern Andrew DeLuca (Giacomo Gianniotti), however they face some problems that many new relationships face . However these problems become much worse for the two when Andrew starts to avoid Maggie . April Kepner (Sarah Drew) returns from Jordan in the premiere wanting to improve her relationship with her husband, Jackson Avery (Jesse Williams), while Jackson doesn't feel the same way and wants to end their relationship . The two start trying to work through their problems and end up have a one - night stand . This results in April becoming pregnant with Jackson's baby, although she does not wish to tell him . Jackson then believes that there is no way of the two working through their problems and wants a divorce, to which April agrees, withholding her pregnancy from him . </P>

Who becomes chief of surgery in season 12