At this moment the deputies sent to Marcellus returned to Syracuse, and assured them that their suspicions were unfounded, and that the Romans had no motive to exercise vengeance upon them. Among the three officers in command in Achradine was a Spaniard, named Moericus. In the procession of deputies, one of the Spanish auxiliaries was deliberately included. This man, finding Moericus without witnesses, began by explaining to him the situation in Spain, whence he had recently arrived. "There everything was in the power of the Roman arms; Moericus could, by rendering them a signal service, obtain the first rank among his fellow citizens, whether he wanted to serve under the Romans or return to his fatherland. If, on the contrary, he persisted in sustaining a siege, what hope was left to him, invested by land and by sea? Moericus, touched by these reasons, had his brother added to the embassy which it had been agreed to send to Marcellus. For this brother of Moericus, the same Spaniard arranged a secret audience with the general, whose word the latter received, and when the plan was well settled, he returned to Achradine.
Then Moericus, to remove all suspicion of treason, asserts that these comings and goings of ambassadors displease him; it is no longer necessary to receive or send anyone; and, for the posts to be better guarded, it is necessary to share the most important among the commanders; in this way each will be responsible for the person whose defense has been entrusted to him. All approved the proposal, and, in the division, the fate fell to Moericus the guard of the district which extended from the Arethuse fountain to the entrance of the great port:he took care to instruct the Romans. On this advice Marcellus had a quadrireme tow a transport vessel loaded with soldiers at night, as far as the Achradine; they had orders to disembark opposite the gate near the Arethusa fountain. The landing was executed on the fourth watch; Moericus introduced the Romans, as agreed. At daybreak, Marcellus gave Achradine a general assault so as not only to attract the garrison of this place to his side, but to oblige that of the island to abandon his post to repel the impetuous shock of the Romans. .
In the midst of this tumult, transport ships, which were kept fully equipped in advance, ready to circumnavigate the island, armed men disembark there; the latter finding the posts empty and the doors left open by those who had just come to the aid of the Achradine, seized, almost without obstacle, the island which the disorder and the flight of its guards had left without defenders. No one put up a less courageous resistance than the defectors, because they mistrusted their very companions; they fled in the middle of the action. Marcellus, on hearing that the island was taken, that a quarter of Achradine was in his power, and that Moericus, with his garrison, had joined his troops, sounded the retreat, in order to prevent the looting of the royal treasury, which was said to be richer than it actually was.