Arco Blathereen was an obese Raxacoricofallapatorian, and the patriarch of the Blathereen family in the 26th century. After he hid in a toxic dump while being hunted by the authorities, Arco could only breathe in poisonous gas. Arco was behind the plan to turn the Justicia system into a massive flame-thrower, to burn other planets and sell the remains as fuel. He was foiled and killed by his half-sister Ermenshrew Blathereen for giving in to the Ninth Doctor's demands so easily.