"Nancy. Don't." Eames warns, looking back at her over his shoulder with a frown. Ghosts in general are a mess, but who knows what you'll get letting one like this in.

If he's a ghost, then this is an illusion. It has to be. Eames doesn't bother trying to get between Nancy and the ghost again, because there's clearly no point to it, instead he tries to focus on seeing through it. Centring himself to find what's hidden.