A secret plan to achieve an evil or illegal end
A conspiracy headed by the patrician Arsaber had a similar issue.
There are even traditions from this period of an actual conspiracy of Panin and Paul against the empress.
The conspiracy group had secret, underground meetings where they discussed their plans.
The conspiracy was discovered; Biron and Auvergne were arrested and Biron was executed.
Pierre saw that there was a conspiracy against him and that they wanted to reunite him with his wife, and in the mood he then was, this was not even unpleasant to him.