There’s also the chance that the someone from Meredith’s past being teased in the trailer is a character we viewers haven’t even met yet. Peter Gallagher is joining the cast of Grey’s Anatomy this season as Dr. Alan Hamilton. We don’t know much about his character, other than he knew Ellis Grey when she was alive, but just that bit makes it perfectly within reason that Meredith also knew him, potentially making Dr. Alan her blast from the past.
