cabal

(noun) a clique (often secret) that seeks power usually through intrigue. Synonyms: faction, junto, camarilla.

(noun) a plot to carry out some harmful or illegal act (especially a political plot). Synonyms: conspiracy.

(verb) engage in plotting or enter into a conspiracy, swear together. Synonyms: conspire, complot, conjure, machinate. Examples: "They conspired to overthrow the government."