In September 2012, the branch's Assassin cell was located in São Paulo. Around that time, the team was compromised by a double agent in their ranks and had to move their safe house at least twice. By September 27, they had begun to suspect that there was a mole in their midst leaking their position to the Templars and alerted the Assassin leader William Miles of their predicament. William in turn relayed this to the Assassin historian and analyst Shaun Hastings, then working with his own cell in Monterrigioni, Italy. Despite the distance, Shaun was trusted to serve as the São Paulo team's lifeline, and it was expected that they would contact him shortly for help.
By 6 October 2012, the São Paulo team had confirmed that there was indeed a mole and, as per procedure, went dark, closing all communications while they dealt with the leak. Shaun noted to his own team that the Brazilian cell would most likely move cities in the meantime and would notify them of their new base once the danger had passed. By April 2014, however, the Assassin headquarters still had not heard from them, and their prolonged disappearance agonized Assassin leaders such as Gavin Banks who by then had seen other cells across the world wiped out.
The loss of contact with the São Paulo team did not hamper the mission of Assassin field agent Desmond Miles when he, Shaun Hastings, and Rebecca Crane traveled to a wrestling stadium in the city to procure the second power source for the Grand Temple on 2 December 2012.
By 2015, the Assassins had managed to gain dominance in Brazil.