Marcus Dixon is an intelligent and strong agent and is fluent in many languages. He is generally level-headed and very keen to the many issues that he must resolve as a leader within the CIA. However, Dixon can be very emotional when his family or loved ones are involved, going so far as to act against orders to protect them.Before he was recruited to SD-6 by Jack Bristow, Dixon was a member of the Recon Marines. At SD-6, Dixon was Sydney Bristow's partner on missions, but unlike Sydney, Dixon was unaware that SD-6 was not actually a covert branch of the CIA. Several times during the first season, Dixon questioned Sydney's loyalties, perceiving the actions she took as being against the U.S. government, when in fact the opposite was true. His cover was that of an investment analyst for Credit Dauphine, a corporate bank in downtown Los Angeles.Dixon forms a bond with Sydney and with Michael Vaughn, who eventually convince him to join the CIA.