The smell expert Oscar Vibenius (Paul Reubens) appears again in Chuck’s life: he’s genuinely intrigued by her peculiar smell. Ned’s dog, Digby, has the same smell. It’s not a coincidence: both of them were brought back from the dead by the Pie Maker.
Oscar asks Chuck if he can smell her hair, because “hair can be so telling about so many things.” There’s nothing sensual in this scene, but the act of smelling someone has a certain intimacy.
Oscar soon realizes what’s the secret of Chuck and Digby: the peculiar “smell of ozone” is the evidence he needs to understand what happened to them.