The chief's announcement of his retirement sparks competition between Derek, Burke, Addison, and Mark. A surgical patient endangers the lives of those surrounding her. Meredith's mother becomes lucid. Cristina and Callie consider marriage proposals. The Denny Duquette Memorial Clinic opens and Izzie cannot wait for the first patient to arrive.
Elenco: Ellen Pompeo , James Pickens Jr. , Chandra Wilson , Justin Chambers , Kevin McKidd , Jesse Williams , Patrick Dempsey , Sara Ramirez , Sandra Oh , Jessica Capshaw , Sarah Drew , Camilla Luddington , Caterina Scorsone , Giacomo Gianniotti , Kelly McCreary , Katherine Heigl , Chyler Leigh , Eric Dane , Kim Raver , T.R. Knight , Jerrika Hinton , Jason George , Isaiah Washington , Kate Walsh , Martin Henderson , Brooke Smith , Jake Borelli , Greg Germann , Chris Carmack , Tessa Ferrer , Gaius Charles , Anthony Hill , Richard Flood .