GREY'S ANATOMY - "Superstition" - When a series of deaths occur at Seattle Grace, the uncanny events bring out the doctors' superstitious sides and make Izzie nervous about Denny's surgery. Meanwhile, Derek and Addison discuss making a more permanent living arrangement, and Richard treats a very special, old friend, on "Grey's Anatomy," SUNDAY, MARCH 19 (10:00-11:00 p.m., ET) on the ABC Television Network. (ABC/SCOTT GARFIELD) KATHERINE HEIGL, JEFFREY DEAN MORGAN