Treatment conundrum: In the glow of last week's surprise Izzie-Alex wedding, Derek happily announced that he knew how to fix Izzie's brain. Unfortunately, the procedure could devastate her memory and speech, even if it saved her life.

Derek told Alex to tell Izzie to have the surgery, while Meredith told Izzie not to. Then Izzie was encouraged by another cancer patient her oncologist had treated with chemotherapy -- only to have that patient suffer complications and wind up on a ventilator. Izzie chose surgery, but insisted on a do not resuscitate order to avoid a similar fate. Read more...

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About the show: The doctors of Seattle Grace Hospital continue their daily challenges for a fifth season of "Grey's Anatomy." "Grey's Anatomy" airs Thursdays at 9 p.m. ET/PT on ABC.

Though rumors swelled that Izzie (Katherine Heigl) gets a brain tumor and is killed off this season, creator Shonda Rhimes says that won't happen. Instead, Izzie will see some romantic sparks with Alex (Justin Chambers) following their season finale hookup. McDreamy (Patrick Dempsey) and Meredith (Ellen Pompeo) will also explore their relationship -- while living together, though Rhimes was mum about who moved in where. Seattle Grace will also get some new doctors, such as Kevin McKidd ("Journeyman"), who plays a military doc on leave and will likely serve as Cristina's (Sandra Oh) love interest.

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"Grey's Anatomy" airs Thursdays at 9 p.m. ET/PT on ABC.