S1, E2: Fungus is distraught after losing track of Mould while on a journey up top. Mould somehow finds his way home but was grabbed by Jessica as he fled through the Bogeyhole, dragging her with him. Bogeydom now faces one of the worst imaginable crisis, a dry cleaner discovering its existence. The Fungus family panics over how they can conceal Jessica, and find a way to return to the surface.