Chosen by the Immortal Elders - Solomon, Hercules, Atlas, Zeus, Achilles and Mercury - Billy Batson is a young boy with a special duty in life. Accompanied by his Mentor, he travels from place to place in a Winnebago learning about life and helping people along the way. When the situation is heading for disaster, all he has to do is to shout the magic word, "Shazam!" and call down the magic lightning that transforms him into the World's Mightiest Mortal, Captain Marvel.