Maximilian is in love with Valentine. Valentine is engaged to Franz.
Valentine's stepmother grows poisonous plants. The count has seduced her and given her a Borgia's Ring with a hidden spike.
It's really not a matter of If, but When and How things fall apart.
The count invites all the others, both youth and adult to his villa.
This is a plot to let Victoria Danglars and Gerard Villefot know that he knows about their secret love child.
The count also reveals to Albert that he has contracted a degenerative disease.