King Tut, currently undergoing psychiatric treatment at The Mount Ararat Hospital with Dr. Denton, escapes during one of their regular sessions when his unending drone bores the doctor asleep. Tut rejoins his gang--Suleman The Great, Florence Of Arabia, and Manny The Mesopotamian--and they rob The Rosetta Stone Company blind of $47,000 and hide out at The Florence Of Arabia Belly dancing Club (closed due to a case of the stomach flu!) run by Florence herself, Tut's new Queen Of The Nile. Here he informs Manny and Suleiman that he has located a deposit of Nilanium, the hardest metal in the world, directly beneath Wayne Manor, and he plans to use the stolen cash to buy an adjacent piece of property from real estate agent Manny and then blast a slanting shaft under the manor! After consulting with Rosetta Stone and The Batcomputer, The Caped Crusader divines King Tut's scheme, and also learns that his shaft is aimed directly at The Batcave and that The Batanium Shield Lining of The Batcave might not withstand the blasting. After telling The Caped Crusadress, Batgirl, to rendezvous with them at Tut's mine, batman and Robin depart via a secret entrance through The Subterranean Blue Grotto Exit, to prevent Tut from spotting The Batmobile.
Meanwhile, Tut's mining foreman, H.L. Hunter, announces that they have struck something way too hard to break through with ordinary blasting. Tut believes they have struck Nilanium, and proceeds to blast it out him. Just then, The Dynamic Trio appear, ready and raring to apprehend The Corpulent King, but Tut and his gang quickly hop into a nearby mining car and speed off down the tunnel. Wanting to preserve their secret identities, Batman and Robin prevent Batgirl from learning what lies within by having her remain behind to keep watch as they race down the tunnel; unfortunately, Tut and his crew has already reached the end of the shaft and crashed right through into The Batcave!!! When Batman and Robin reach the bottom of the shaft, Tut and his men confront them with their knowledge of their true identities! After a short Batfight, Batman spritzes the place with Batnesia Gas to erase whatever memory of The Batcave The Tutlings have, and then orders Alfred to bring them to the front lawn. But Tut has already escaped up the tunnel during the battle and The Caped Crusader and The Boy Wonder chase him in hopes of capturing him before he gets a chance to spill the beans, but all and alas to no avail. Just as The Nefarios Nabob is about to announce the true identities of Batman and Robin, he is done in by his own loud voice, which vibrates a rocks from the roof which knocks him unconscious. Tut comes to, reverts to his naturally scholarly self and to the Dynamic Duo's relief, has absolutely no recollection of his past experience!