Cato glanced at the Emperor and dimly recalled seeing his stepson drift towards the rear of the box a while earlier. Nero’s mother was on her feet clapping her hands with delight while the Emperor beamed. The Praetorians’ cheering gradually synchronised into a repeated roaring of his name. ‘Nero! Nero! Nero!’

The boy made a slow circuit of the arena, sitting haughtily in his saddle as he revelled in the cheers. Macro nudged Cato and pointed to the imperial box.

‘There’s one who is not so happy.’

On the dais, beside his father, was young Britannicus; his expression hardened into a cold scowl and his right hand balled into a tight fist. He only relaxed when his rival finally left the arena and the Praetorians ceased cheering. Noon had passed and the editor announced a short interlude while the targets were removed and the arena prepared for the main entertainment of the day, ten gladiator bouts culminating with a fight between a secutor known as the ‘Dove’ - the current darling of the mob - and the ‘Neptune of Nuceria’, a retiarius. A handful of those in the imperial box hurried down the steps to relieve themselves or take refreshment in the area beneath the box.

‘I’m going for a quick piss,’ Macro announced, standing up.

Cato nodded as his friend squeezed past and made his way down the stairs and along to the head of the staircase leading out of the arena. Cato’s mind was still preoccupied with the expression he had caught on Nero’s face just before he had left the arena. There was no mistaking the light of ambition that burned there. It had been a calculated performance in front of the Praetorians and for the moment he was their darling.

Macro shook himself off and lowered his tunic. The latrine block was filled with men who were taking advantage of the intermission. He made his way outside towards the gate giving out on to the parade ground. He picked his way through the litters and the slaves squatting silently beside them until he came to the enclosure beneath the imperial box. Two German guards stood either side of the heavy red curtain flaps that covered the entrance. As Macro approached, one of them held out his hand and spoke in his harsh tongue.

‘Easy there, Herman,’ Macro growled. ‘Just passing by. Don’t get your beard in a bloody twist.’