Egghead, Queen Olga and The Cossacks raid The Gotham City Radium Center and rob 2 lbs. of radium. Later, as Barbara Gordon visits her friend Professor Dactyl at The Gotham Museum, Egghead and Olga grab a giant fossilized 40 million year-old Neosaurus egg, unbeknownst to Barbara or Dactyl! Barbara alerts her dad of the egg's theft, and he in turn alerts The Dynamic Duo. As The Caped Crusader and The Dominoed Daredoll ponder the problem, Egghead plans to hatch the egg with the radium and release the monster on a rampage of Gotham City! At the same time, Batman and Batgirl remember Professor Grimes' article on revitalizing fossils ("Revitalizing Fossil Forms By The Use Of High-Energy Radioactive Energy Sources," which appeared in an issue of The Southeastern Regional Journal Of Applied Radiology) and, uncovering Egghead's plot, use their Batgeiger counters to track down the radium to Egghead's hideaway. Leaving Batgirl and Robin to enter the front way, Batman sneaks around to the back entrance.

Entering the hideout, Batgirl and Robin are quickly captured and forced to watch as Egghead succeds in hatching the egg. Egghead then tries to offer the pair as a snack to the hatched beast, but the moster advances towards him instead! Egghead, Olga, and her Cossacks turn chicken and gladly turn themselves in to the waiting paddy wagon outside. As Batgirl and Robin prepare to take on the monster, they are uprised to see it remove its head and reveal the weclome countenance of Batman, who, knowing that it was impossible to hatch the egg, decided to use Egghead's scheme against him. So, he donned a Neosaurus costume, secretly entered the egg, and made it look like Egghead had really hatched a monster!

As Bruce, Dick, O'Hara and Gordon chow down on Barbara's birthday cake, she recieves a call from her surfer friend, Skip Parker...just as The Joker and his cohorts Riptide and Wipeout arrive at Gotham Point by Jokemobile...