O'Connor is an enlisted soldier aboard the USS Nathan James. His rank is that of a Petty Officer Third Class.O'Connor is young and still learning his way in the Navy. He is often seen doing deck work on the ship in coveralls and a red baseball cap with the ship insignia, which is won by the engineering staff. He is smart and resourceful, and is friends with Griffin, who is of a similar age and rank.O'Connor was the catalyst for the crew of the Nathan James retaking the ship when it was held hostage by the Maryland State troopers in Baltimore, on orders of Amy Granderson. When the entire crew was being herded from the deck into the ship, O'Connor ran and jumped overboard while being shot at. He resurfaced later on the ship (he explained to Cruz and Griffin that he climbed up the anchor chain and came over the bow) and turned the heating system way up in order to distract the troopers. When Cruz and Griffin escaped the troopers, they ran into O'Connor, and all three broke into the armory and loaded up on weapons and night vision goggles for the rest of the crew. The three men, with an unknown assistance from XO Slattery, killed the troopers holding the rest of the crew hostage and helped imprison the rest.O'Connor often pays his respects to fallen soldiers in the on-deck memorial services.