Peter, one of the North American agents is killed as he sends a desperate message to Simon. Simon and Mary go to New York to investigate. On arrival at the apartment Mary finds what she thinks is Simon's dead body. However, the body is Peter, as most of the agents on Earth look like Simon. Simon sees this as confirmation that whoever they are up against knows they are there and are laying a trap. Peter was posing as Doctor Westhoff, a member of a Think Tank set up to discuss ways of reducing the worlds population. Simon decides to spring the trap and takes Peter's place in the Think Tank... (thetvdb.com)