But to do so, they need three elements. One element only exists 10,000 years in the past. One exists 10,000 years in the future. The last exists in the present. In fact, it's actually the same element--just in different forms during different time periods because of radioactive decay.
Since time travelling in the Fawcett Comics universe involves zipping around the Rock of Eternity, the wizard Shazam spots the Sivanas as they travel to gather up the elements. He warns the Marvels and what follows are three mini-adventures, all involving the continent of Atlantis (either above or below water depending on when) and all involving scientists who are members of the
Well, the Marvels can't depend on their super powers, but they can still use their brains. So maybe--just maybe--they can turn the tables on the bad guys.