Green was the captain of the ship Draco, one of the British Imperial Fleet that landed on the Moon. Of all three captains, Green appeared to be the one most inclined to stick to protocol even amid the changes required for space travel, requiring evidence of the impracticalities of standing in space before he tolerated crews being strapped to their stations even while the ship was in flight.
After the Draco was shot down while trying to travel to an alien citadel, Green led a group out to search the forest. After six of the men were killed following a few hours of travel, Henry Stanton, the astral pilot, requested to return to the ship on the grounds that he was now the only helmsman left for the Draco, but Green dismissed this as cowardice due to his inability to acknowledge the complexity of piloting a ship. Before the matter could be settled, a large creature stomped through their location, trampling most of Green's men, although Green himself was unintentionally suffocated when he kept calling for help due to the agony of his broken leg and Stanton forced his mouth shut to try and keep him quiet. (PROSE: Imperial Moon)