The third series of the Emmy- and Golden Globewinning medical drama continues, following the trials and tribulations of Meredith Grey (Ellen Pompeo) and her fellow interns at Seattle Grace Hospital. In this week’s episode, George’s father prepares to undergo his second operation; Izzie bonds with an angry teenage patient; and Alex returns to obstetrics.

It is another difficult week for George, who is counting down the days before his father undergoes massive cancer surgery. The cardiac procedure on Mr O’Malley went well, which prompts his overjoyed family to organise a bedside celebration for him – but the patient is by no means out of the woods. The surgeons will not know what his future holds until they begin the procedure and see how far the cancer has spread: if it has progressed too far, they will have to call a halt to the treatment.

When Mr O’Malley is told about his potentially bleak prognosis, he begs Webber to continue with the surgery even if things look bad. “I can survive this,” he insists. “I know I can. O’Malleys – we’re fighters!” Webber tries to protest, telling him that he is bound to act in the best interests of the patient, but Mr O’Malley will not accept that. “Closing me up and sending me home to die is not what’s best for me,” he says. “Not medically, or any other way.” Will Webber stick to his guns, or will he agree to Mr O’Malley’s request?

Izzie is also dealing with a difficult patient: 17-year-old Heather, who has VATER syndrome – an association of birth defects – with such severe scoliosis that she is almost bent double. Heather is in for two procedures: one to relieve pressure on her lungs, and another to remove kidney stones. When Izzie tells Heather that the operations should improve her quality of life, the bitter young patient replies frostily: “I don’t think doctors should make promises they can’t keep.”

Despite a rocky start, Izzie and Heather eventually bond. When Izzie tells Heather about her problems following Denny’s death, the teenager grows to like her doctor. “So much for my theory that life doesn’t suck for pretty people,” she concedes, apologising for her previous spikiness. Things seem to be improving for Heather when Callie convinces Derek to agree to a risky operation that could improve her life immeasurably. “Are you messing with me?” asks Heather suspiciously when Derek tells her he could make her walk upright. “It’s not nice to mock crippled kids.” However, when Heather’s insurance company puts up a fuss due to the experimental nature of the surgery, it looks like her future may be bleak.

Elsewhere, Alex finds himself working with Addison again after incurring Mark’s wrath by fetching him the wrong coffee. Exasperated, Mark tells Alex that he can go back to the “squishy and pink” world of obstetrics – he clearly is not cut out for plastic surgery. Alex is not bothered, especially when Addison welcomes back her former sidekick by telling him that she has an “amazing surgery” lined up on which he can scrub in. Has the world of plastics finally lost its appeal for the cocky young intern?

Also this week, Meredith finds it hard to deal with seeing her estranged father around the hospital. Webber encourages her to break the ice, but is she really ready for this step? Izzie makes a momentous decision regarding the $8.7million that she inherited from Denny. Cristina and Burke refuse to speak to one another following Burke’s surgery. Addison and Alex surprise each other. And the doctors are in for a big shock when Mr O’Malley’s operation finally gets underway.