Ideas
* I could feel the water rising, but with my arms tied behind my back, I didn't know if I could make it out alive.
* She jumped off the bridge just as I reached out. I felt her fingers glide out of reach and I...
* I was sat waiting for her on the bench near the river, when I spotted a......
Naomi Adams
I am you?...And you are me?
You bump into someone on the street while looking down. You both hit heads really hard, and when you "wake" or get your grounds again, you're in their body like your consciousness(or soul I guess) jumped from your body to the other person's body... If you wanted to make it even more interesting, you could just have your consciousness jump to the other person's body, but their's doesn't go anywhere, so there are two consciouses(I don't think this is a word) in the stranger's body (including yours).