I'm pretty sure that this is pure specualtion, rather than any spoilers, as it is based on existing information.
Could River, after her death and 'input' into CAL (the supercomuter / virtual world in Silence in the Library) become the 'Papal Mainframe' and defacto 'power that is' / authority in the Church?
I realise that there is a rather large element of timey-wimey necessary to make it happen but I do think that Moffat is evil enough to make Melody the hero and villain at the same time.
Could River, after her death and 'input' into CAL (the supercomuter / virtual world in Silence in the Library) become the 'Papal Mainframe' and defacto 'power that is' / authority in the Church?
I realise that there is a rather large element of timey-wimey necessary to make it happen but I do think that Moffat is evil enough to make Melody the hero and villain at the same time.
