<P> "Wishin' and Hopin"' is the fourteenth episode of the third season of the American television medical drama Grey's Anatomy, and the show's 50th episode overall . It was written by Tony Phelan and Joan Rater and directed by Julie Anne Robinson . The episode originally aired on the American Broadcasting Company (ABC) in the United States on February 1, 2007 . In the episode, Dr. Meredith Grey (Ellen Pompeo) struggles with her Alzheimer's - stricken mother, Ellis Grey (Kate Burton), becoming temporarily lucid . Further storylines include Dr. Izzie Stevens (Katherine Heigl) and Dr. Miranda Bailey (Chandra Wilson) continuously seeking patients for their new clinic, Dr. Richard Webber (James Pickens, Jr .) dealing with the repercussions of his upcoming retirement, and Dr. George O'Malley (T.R. Knight) facing negative response from colleagues on his unexpected marriage to Dr. Callie Torres (Sara Ramirez). </P> <P> Although the episode was fictionally set in Seattle, filming occurred in Los Angeles, California . Burton reprised her role as Dr. Ellis Grey in a guest star capacity, in addition to Sarah Utterback, who portrayed Olivia Harper . The title of the episode refers to the song "Wishin' and Hopin"', by British pop musician Dusty Springfield . The episode received mixed to favorable reviews, with the storyline involving Ellis being particularly praised by television critics . Upon its original airing, the episode was watched by 24.18 million viewers in the United States, ranked first in its time - slot and garnered an 8.5 Nielsen rating in the 18--49 demographic . </P> <P> "Wishin' and Hopin"' opens to a voice - over narration from Dr. Meredith Grey (Ellen Pompeo) about extraordinary events . The Denny Duquette Memorial Clinic has been opened, after a US $8 million funding from Dr. Izzie Stevens (Katherine Heigl). Four of the hospital's attending surgeons, Dr. Derek Shepherd (Patrick Dempsey), Dr. Preston Burke (Isaiah Washington), Dr. Addison Montgomery (Kate Walsh), and Dr. Mark Sloan (Eric Dane) are all seen competing for the position of chief of surgery, after the current chief Dr. Richard Webber (James Pickens, Jr .) announces his plans for retirement . Meredith arrives to the Alzheimer's support home that her ill mother Dr. Ellis Grey (Kate Burton) is living at, and to her surprise, her mother has become lucid, but faints . Ellis is taken to Seattle Grace Hospital, her former source of employment . Residents Dr. Cristina Yang (Sandra Oh), Dr. Miranda Bailey (Chandra Wilson), and Dr. Alex Karev (Justin Chambers) are awaiting the arrival of patients at the clinic, and Dr. George O'Malley (T.R. Knight) walks in to announce his unexpected marriage with Dr. Callie Torres (Sara Ramirez). </P> <P> A cancerous patient, Marina Wagner (Amanda Collins), is admitted into the hospital and is revealed to have toxic blood - presumably caused by a chemical reaction between an herbal supplement and chemotherapy - making several physicians fall ill . O'Malley is exposed to the neurotoxin, and quickly becomes anxious, fearing that his marriage is the cause of the sickness . Ellis is diagnosed with a heart condition, in which surgery or medication are options . Ellis does not want the surgery, but Meredith fears that she will not be compliant with her medication . Shepherd and Burke try to close up Wagner as the OR was evacuated before her surgery was completed, by entering the operating room with sealed, airtight suits . Ellis agrees to the surgery, but opts to speak with Webber, her former lover . A teenage patient is brought into the clinic by her father, hoping that a doctor can teach her how to use tampons . When her father leaves the room, she explains to Bailey that she had sex, but her pregnancy test is negative . Shepherd and Burke run out of air whilst operating on Wagner, so Yang, Stevens, and Meredith enter holding their breath to close the patient's incision . O'Malley's colleagues act in a rude manner to his new marriage, and displeased, he lectures them, standing up for Torres. Sloan is seen to be having sex with Montgomery, and Yang agrees to marry Burke . At the conclusion of the episode, Ellis' lucidity has vanished, leaving Meredith and Webber distraught . </P>

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