Delos was a slave in Rome. He was partnered with Ian Chesterton when the two worked as oarsmen on a galley in July 64. When the ship was destroyed in a storm, he rescued Ian. Ian announced his intention to go to Rome, and Delos decided to accompany him.
In Rome they were captured and were made gladiators and they were forced to fight each other to the death. Delos had Ian at an advantage, but instead of killing Ian, he lunged at Nero. In the scuffle, Delos and Ian escaped. Later that evening they headed for Nero's palace to rescue Barbara Wright. After the rescue, Delos headed north for part of the journey with Barbara and Ian, and then headed for home. (TV: The Romans)