An underground activist group says it plans to start openly doxing billionaires as part of a phased campaign against what it calls the American oligarchy—beginning this month with a release that maps the homes of Elon Musk, his brother Kimbal, and Tesla’s board, alongside investors and suppliers that keep the corporation afloat.

Two of its members, interviewed by WIRED on the condition of anonymity, say they spent the past year constructing dossiers on billionaires—and one trillionaire—and the people they consider their top lieutenants, using nearly every method available to a private investigator, and some that are not.