The interns help Izzie keep Denny alive after she's cut his LVAD wire. Derek must perform surgery on Burke's shoulder and risk doing irreparable damage to the nerves. Cristina freezes in the O.R. during Burke's surgery. The chief discovers his niece's cancer has returned. Alex fights for Denny's heart at Mercy West, eventually offering Dr. Hahn the chance to scrub in at the surgery as Burke has been shot. Before surgery, Denny asks Izzie to marry him. However, after the heart has been inserted, it does not beat and back in Derek's OR, Burke still cannot move his fingers.