...on Ethan's character's body somewhere towards the end of the film; What did that mean? My memory's a bit foggy, but he did state that him and her were the same person, right?
Can someone sum up the plot and explain it nicely?
Yes, Sarah Snook character and Ethan character are the same person, and this was the twist of the movie. Right before the end they show you a timeline going from baby Jane, to little Jane, to young Jane, to after-sex-change Jane, to the person with burned face, to the person with scarred face, and then to the Ethan Hawk character.
About the loop that happens through all the movie, I'm still trying to completely understand it so I don't think I'm the best person to explain it to you, sorry.