<Tr> <Td_colspan="2"> List of Grey's Anatomy episodes </Td> </Tr> <P> The eighth season of the American television medical drama Grey's Anatomy, commenced airing on the American Broadcasting Company (ABC) on September 22, 2011, with a special two - hour episode and ended on May 17, 2012 with the eighth season having a total of 24 episodes . The season was produced by ABC Studios, in association with Shondaland Production Company and The Mark Gordon Company, and overseen by showrunner Shonda Rhimes . </P> <P> This season follows the story - line of Meredith Grey (Ellen Pompeo) and Derek Shepherd (Patrick Dempsey) as they try to save their marriage and adopt Zola after Meredith tampered with the Alzheimer's trial in the previous season . Miranda Bailey (Chandra Wilson) also struggles to forgive Meredith because Richard Webber (James Pickens, Jr .) takes the blame for Meredith and stepping down, and Owen Hunt (Kevin McKidd) takes his place as Chief of Surgery . Cristina Yang (Sandra Oh) decides to have an abortion, putting her relationship with Hunt at odds . Callie Torres (Sara Ramirez) and Arizona Robbins (Jessica Capshaw) co-parent their baby with Mark Sloan (Eric Dane) who continues to have an on / off relationship with Lexie Grey (Chyler Leigh). Alex Karev (Justin Chambers) deals with the fallout of his decision to tell Owen about Meredith altering the Alzheimer's trial, and becomes an outcast by the other residents . Teddy Altman (Kim Raver) marries Henry Burton (Scott Foley), who later dies of a heart condition, leaving her devastated . </P> <P> The season hit the series' low for ratings as it ended with an average of 10.92 million viewers ranking at no . 34 and in the 18 - 49 key demographic ranked at no . 12 . Loretta Devine garnered critical acclaim for her portrayal of Adele Webber and earned numerous nominations including the Primetime Emmy Awards for Outstanding Guest Actress in a Drama Series and the Critics' Choice Television Awards . James Pickens, Jr. won Outstanding Supporting Actor at the NAACP Image Awards, and Chandra Wilson and Sandra Oh both received nominations for Outstanding Actress in a Drama . Stacy McKee was nominated for Humanitas Prize for writing White Wedding . Sara Ramirez was nominated at the 13th ALMA Awards for Favorite TV Supporting Actress . For the 38th People's Choice Awards, the show was nominated for Favorite TV Drama, and Ellen Pompeo and Patrick Dempsey were respectively nominated for Favorite TV Drama Actress and Favorite TV Drama actor . </P>

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