Artist Steve Rogers is nearly murdered by spies, seeking his late father's national secrets. He is saved during surgery via a secret formula; this serum not only heals him but also gives him fantastic strength and lightning reflexes. To help solve the mystery behind his father’s murder and bring those guilty to justice, a government agency equips him with a special motorcycle loaded with gadgets and an indestructible shield. Now armed, he battles against the nation's enemies as the Sentinel of Liberty, Captain America.