A recipient of an experimental body enhancement chemical retaliates against his would be killers as a star spangled superhero.
When Steve Rogers, 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 heals him but gives him tremendous strength and lightening reflexes.
To help Rogers retaliate against his attackers, a government agency equips him with a special motorcycle loaded with gadgets, including a detachable shield that's not only bulletproof, but can be thrown as a weapon.
Thus armed, he battles against the nation's enemies as the Sentinel of Liberty, Captain America.