Cato steered aside so that they passed each other by a safe margin and continued following the gang leader. Cestius continued for a short distance before he looked round quickly. Then, seemingly satisfied that no one was watching him, he made for the guarded entrance of one of the warehouse compounds. He nodded a greeting to the man at the gates, who heaved one open to admit his visitor and then drew it shut once Cestius had disappeared from sight. Cato felt a surge of panic at the prospect of losing his quarry. He stopped on the wharf opposite the gates and squatted down and retied the lace of his boot as he looked over the gateway. A sign was painted on the wall next to the heavy timbers of the gates announcing that the warehouses were rented out by Gaius Frontinus. It invited interested parties to apply at his offices in the Boarium.

Cato drew a deep breath to steady his nerves and strode up to the gates. The guard stirred and moved to block his way. He was a thickset man with a scarred face and Cato guessed that he must be one of the many former gladiators who turned up in such roles after they had won their freedom, or been discarded by their trainers.

‘What do you want?’ the guard demanded without any preamble.

‘I’m supposed to meet my master here, sir,’ Cato replied. ‘I saw him enter just a moment ago.’

‘Really? So what’s his name then?’

Cato opened his mouth and caught himself just in time. If Cestius was in disguise then there was a strong possibility that he was using a false name as well. If Cato tried to use his real name the guard would refuse him entry. Worse still, he might mention it to Cestius on the way out and thereby alert him to the fact that he had been followed.

The pause was long enough for the guard to reach a decision. ‘Thought so. You’re a chancer. Now turn away and piss off. Before I make you.’ He patted the studded club swinging from his belt.