Plasus was the high advisor of Stratos, the capital city of the Federation member-world Ardana in 2269. He followed a policy of apartheid against the Troglytes, the miner-class on the planet Ardana. He believed the Troglytes as inferior, intellectually and physically, and denied them many privileges the Stratos city-dwellers had. When the Troglytes formed a resistance, he was not above torture to crush the resistance. Even his own daughter, Droxine, questioned his methods.