When a commercial artist is almost murdered by spies looking for his late father's secrets, he is saved in surgery when the FLAG formula is injected into him. This serum not only healed him but also gave him tremendous strength and lightening reflexes. To help him retaliate for his attack, a government agency equipments him with a special motorcycle loaded with gadgets and a detachable shield is not only bulletproof, but can be thrown as a offensive returning weapon. Thus armed, he battles against the nation's enemies as the Sentinel of Liberty, Captain America.