He is portrayed by Benicio Del Toro.
Hallam is a former student of L.T. Bonham, a trainer of military assassins, but went rogue after suffering from severe battle stress from his time spent fighting in the Kosovo war. After committing two murders, Hallam is apprehended by the authorities who convince Bonham to join them in their search. Bonham locates Hallam at a forest den he had been living in, and they fight. The authorities then move in and successfully capture Hallam before interrogating him. Hallam claims that he is under threat from the Army due to unofficial assignments he had previously been involved in, and soon enough various government agents arrive with proof that they may take possession of Hallam. As Hallam is being driven away by the agents, he strangles one of them with his chains and causes the van to crash. With all the agents dead, Hallam escapes unharmed.