At around seventeen years of age, Chris joined the United States Air Force, serving as a pilot and marksman. In addition to flying fighter planes, he demonstrated outstanding firearms handling and was trained rigorously in hand-to-hand and knife combat, and took part in missions overseas. He has been described by his commanding officers as "uncompromising", "possessing unwavering dedication" and having a "high level of adaptability". However, Chris was constantly coming into direct conflict with his superiors. Unable to settle these disputes, he chose the path of early retirement at around 23–24 years of age.
After leaving the Air Force, Chris started drifting across the US and eventually got to Raccoon City; where his old comrade, Barry Burton, suggested he try out for the new S.T.A.R.S. force of which he had recently joined - an elite unit mostly comprised of ex-military personnel, and created to quell the increase in the number of cases involving terrorism. Thinking he may as well try out, Chris applied for S.T.A.R.S. where he was immediately accepted. Along with Barry, Chris was recruited into the lead Alpha Team with Albert Wesker as captain.
He served as both a point man (PM) as well as Alpha team's co-pilot, and was known for his marksmanship ability (for which he had a friendly rivalry with Bravo team member Forest Speyer and received numerous commendations for). It was here that he also met his future partner and closest friend, Jill Valentine, and the two bonded with each other.