The lion jumped on the retiarius and tore off his head, helmet and all. Disappointed with the visor over the face, the lion tossed the head aside. Emperor Trajan watched from his box as the head rolled slowly across the sand and came to a stop against the wall, leaving a winding trail of stark red blood behind it. The crowd cheered and yelled, shaking their fists or clapping, some on their feet, others in their seats, others jumping up and down. The lion, having disposed of the head, proceeded to gnaw into the rest of the body. ‘More gladiators!’ Trajan commanded, to the lanista standing at the side of the arena. The man nodded and disappeared into the tunnel in the wall of the arena to fetch the requested gladiators. The last gladiator who remained came up behind the lion slowly, with a sword in one hand and a shield in the other. The lion, engrossed in the consumption of its victim’s torso, did not notice his approach until the gladiator stabbed down through the back of the beast’s neck. The lanista reappeared from the darkness of the tunnel and ushered out four more gladiators who immediately began hacking at each other. Emperor Trajan watched excitedly as one gladiator knocked another to his knees, drew back his sword and drove it straight through his throat. Something tapped Trajan on the shoulder. Trajan looked around. A man in a dark brown cloak stood behind him in the box with a hood pulled down over his forehead and eyes. ‘What is your name, and what are you doing here?’ Trajan asked sternly. The cloaked man did not reply to either of those questions but reached inside his cloak and drew out a small wooden box which he proffered to Trajan. Trajan stared at it then turned to the Praetorian Guards stationed at the corners of the box. ‘Dispose of this man,’ he commanded. But they did not respond. It was as if they hadn’t heard him. ‘Dispose of this man!’ Trajan ordered again, more firmly this time. But still his guards were not moving. Trajan turned back to the cloaked man. ‘What trickery have you done to cause this?’ ‘I have done no trickery,’ the cloaked man replied. ‘I have done something far more advanced than that.’ He proffered the box again. Trajan was struck by his unusual accent. He had not heard anybody speak with such an accent in all his life. He glanced down at the box then back up at the cloaked man then down at the box again. Cautiously, he took it and examined it from all sides. ‘You need not examine the box,’ said the cloaked man. ‘It is of no importance. Its contents are what you should be examining.’ Trajan narrowed his eyes at the man then opened the box with a creak. Inside was a small block of some heavy metallic substance, smaller than Trajan’s hand, along with three small boxes. Trajan lifted out the block of metal delicately and peered at it. There was a thin bar of metal curving from the front piece to the bottom piece and behind the bar was another metal protrusion. Trajan pressed it, and it slid back with a click. ‘What is this object?’ Trajan exclaimed, stupefied. ‘Allow me to demonstrate,’ said the cloaked man, snatching one of the small boxes, opening it and reaching inside, extracting a small golden cylinder. He plucked the block of metal from Trajan’s hand with long, tanned fingers, and loaded the cylinder into it. ‘You might want to block your ears,’ the man said, and Trajan, puzzled, did so. The cloaked man then held the object with both hands at arm’s length, aiming across the arena, and pulled the trigger. There was an explosion like nothing Trajan had ever heard before. A plume of smoke burst from the front of...