1 - Mary is out and standing in the hallway in a pile of splintered door. She is now a Shifter and she looks mad as hell (perhaps one hand on the ground in an animalistic three-point stance). Chris, still sitting, has her hands out in a placating manner.
2 - Mary dives and lands on top of Chris, scratching her up. Chris has her arms up to protect her face / upper-body.
3 - Chris manages to get a hand up under Mary's chin, trying to push her away and off.
CHRIS: I know part of you is still in there.
4 - Mary rakes at Chris's arm, causing her to loose her leverage. Blood flies from the wound
CHRIS: And you need to know that I love you--!
5 - Mary sits on top of Chris's prostrate form, hands raised to claw the heck out of her. Chris looks up at her sister, accepting her fate, whatever it may be.
CHRIS: ...And I always will.
Start from the beginning.