"I believe in magic," because she has definitely seen that with her own two eyes, even if Jane calls it science, "so I guess ghosts wouldn't be much of a stretch? Ghosts are never my first suspicion." Though in this case... Well, that was just strange. People aren't meant to walk through other people, but Darcy fancies Jane Foster's face lighting up and giving a perfectly scientific explanation for such a phenomenon. Which makes her smile for a brief moment in spite of herself.

"You have a theory?"