He posed as Joseph Green, after killing the previous Prime Minister, as well as Green himself, becoming Acting Prime Minister. General Asquith, disappointed with his poor leadership, tried relieving Jocrassa Fel-Fotch of command under the Emergency Protocols. He along with his sister Blon and his brother killed Asquith, with the latter Slitheen using his skin as a skin suit. When the alien experts were gathered together in 10 Downing Street following a faked crash of the Slitheen's own ship, Jocrassa Fel-Fotch pressed a button electrocuting their ID badges, (TV: Aliens of London) and rendering the emergency protocols in dealing with extraterrestrial encounters useless. All except the Ninth Doctor were killed.