<P> In this episode, Shepherd is involved in an accident while attempting to help the victims of a car accident . He is later pronounced brain dead, in part due to the surgeons not providing him with a timely CT scan . "How to Save a Life" has the fewest series regulars appearing in an episode, with only six regular cast members in it: Ellen Pompeo, Patrick Dempsey, Chandra Wilson, Kevin McKidd, Sarah Drew and Caterina Scorsone . This episode also marks the first appearance of Dr. Penelope Blake (Samantha Sloyan). </P> <P> The episode's original broadcast was watched by 9.55 million viewers and registered the show as the week's highest rated drama and third - highest rated scripted series in the 18--49 demographic . It received mixed reviews from the critics who were divided on the show's handling of Shepherd's death . However, they were largely laudatory of Pompeo, with critic Rick Porter deeming it the best performance of her career . </P> <P> The episode opens with a flashback of a five year old Meredith Grey (Ellen Pompeo) lost in a park . In the present, Dr. Derek Shepherd (Patrick Dempsey), leaves Grey and their two children to go to Washington to resign from the President's brain mapping project . While she is at Grey - Sloan, Derek is on the phone with his sister, Dr. Amelia Shepard on speakerphone while in surgery as he drives to the airport, and the two speak briefly until his phone loses its signal . Shortly thereafter, Shepherd witnesses a road accident and stops to help the victims . He rescues a young girl named Winnie (Savannah Paige Rae), and helps her mother who has a dislocated leg . With assistance from Winnie, he rescues another couple from their car right before it explodes, and offers them emergency medical care . </P> <P> Paramedics arrive at the scene and transport the victims to a nearby medical health facility at Dillard . Shepherd returns to his car and stops briefly in the middle of the road to answer his cell phone . While doing so, his car is hit by a semi-trailer truck . Shepherd is transported to the same hospital at Dillard, with multiple fractures, internal injuries, and loss of speech . His thoughts are verbalized through narration . Shepherd realizes that he needs a CT scan for his head injury, but cannot tell the ER staff . Instead, they transport him to the operating room to address his abdominal injuries . By the time of the surgery, Shepherd is certain that he will die as his hemorrhage will not be discovered in time . One of his doctors, Dr. Penelope Blake (Samantha Sloyan), wants to perform a CT, but is dismissed by an ignorant senior . The hospital's neurosurgeon takes over an hour to arrive, and by the time he arrives Shepherd is already brain dead . He dismisses Blake, who was the only doctor on Shepherd's case to have devised the right treatment plan . </P>

How to save a life grey's episode