Phil Dexter is a former S.H.I.E.L.D. agent and ally of Natasha Romanova aka Black Widow. He was fired by Nick Fury for drinking on the job and disobeying orders. Though the his reason for disobeying those orders might have been justified. When someone tries to kill Romanova she calls Phil to help her uncover the reasons why. Due to his working in the spook rooms for SHIELD and his info gathering skills he was a perfect choice. Plus he owed Natasha. He found out the info and accompanied(somewhat forced) her on her journey. On the way they also come upon young runaway Sally Anne Carter, who was being attacked by two truckers she was hitchhiking with. Dexter was willing to leave the girl saying, working for Fury he had seen and experienced much worse than what would happen to her.