You're an immortal who's lived through thousands of years of human history. Each time you die, you reincarnate with all your past memories. Today, for the first time ever, you meet someone who recognizes you from a previous life.

Random person: “Oh my god, I haven’t seen you since 1270 AD. Why didn’t you tell me you were immortal? I thought you died.”

You: “I’m sorry but, who are you? How do you know me?”

“Oh, silly me. Of course you don’t recognize me. I'm The Doctor.”