The Kavanaugh sisters. All powerful beings that help keep balance in the world. The only things that can stop them, are themselves, or their 'father.' Otherwise, they can't be stopped.
Except, for one thing. It's called 'Darkness'
The Kavanaugh sisters all fear 'Darkness' except for the eldest, Cicely.
Cicely doesn't fear 'Darkness.'
So when 'Darkness' endangers the one Cicely loves, will she choose between saving the love of her life, or pleasing her 'father' by continuing her duties as the eldest Kavanaugh sister?