In Skulduggery PleasantSkulduggery Pleasant, Mr. Bliss betrays SkullduggerySkulduggery and steals the key for Serpine.
However However, we find out that he only did this so he would be able to predict Serpine's actions and try to stop him.
Why didn't he tell SkullduggerySkulduggery or the council his plan?
The They might have been able to help or at least avoid the panic that his perceived betrayal might have caused.