The Most Heartbreaking Character Exits on Grey's Anatomy, Ranked

The first patient who really becomes a character, Denny, is also the first major death that broke our hearts on Grey's. The young heart patient quickly befriends his doctors and falls in love with Izzie. When his condition takes a turn for the worse, Izzie risks her career to cut his LVAD wire and move him up the transplant list. It works at first, and he gets a new heart and proposes to Izzie, who accepts. Alas, their fairy-tale ending was not to be: when Izzie stops by to show him her "prom" dress ahead of a big event, she finds that he died suddenly from an unexpected complication. We'll never be able to listen to "Chasing Cars" without sobbing.