Owen T. Matthews is a programmer and the creator of the Black Market Bazaar.
Owen created the Black Market Bazaar, an online drug marketing system. Several conflicts began within the time period of the site's heaviest production, while Owen was discovered by the ISA. They wanted to use the site's money to fund themselves and set Owen up under the pseudonym "The Sphinx", the mysterious and publicly unknown head of the site, and gave him 20% of his profits back. Owen, however, planned to go public with the site and the ISA targeted him, worrying that they will be exposed and thus make him a threat to national security.
Owen's activities fell under the investigation of Interpol, which was tracking Rafael Hernandez, a drug smuggler who was after the Sphinx. Owen lived under the false claim that he simply met the Sphinx and is the only one who can identify him, so Interpol believed that such information could ultimately lead them to Rafael. Owen was apprehended by Interpol agents in his home and taken on an international flight to Rome.
Since Owen was a threat to national security, he was a Relevant Number and the Machine somehow diverted this information from the government and over to Reese and Finch. Following the death of Carter, Reese was planning on leaving the team and didn't know that the Machine tampered with the flight scheduling and placed him on Owen's flight. Reese got a text on a businessman's phone saying "4C" - Owen's seat number. Owen was attacked by a member of Rafael's gang, but Reese was able to save him.
Over the course of the flight, various parties somehow involved with the Black Market Bazaar sent assassins after Owen, including an ISA agent who acted as a successor to former member Sameen Shaw, who was helping Finch investigate back in New York. Owen did not reveal he was the Sphinx until Reese defeated the ISA agent a second time. Meanwhile, Carlos, a flight attendant, was revealed to be one of the assassins and hijacked the plane.
Reese fought Carlos while Finch used a flight controller to steer the plane to safety. In Rome, Reese snuck Owen there by hiding him in the luggage. He provided him with enough resources to stay in Rome and live a safe life. Reese declined Owen's offer of payment, leading Owen to realize that Reese's job is helping people.