Abbott and Costello Meet the Monsters!

After overhearing Dr. Gustav Zoomer explain the legend of Klaris the mummy and the sacred medallion that points to treasure, Abbott and Costello decide to go to his house to apply for a job accompanying the mummy back to America. They hope this will give them a way out of being stranded in Cairo and a chance at securing some of the treasure.

Just before Abbott and Costello arrive at Dr. Zoomer's house, two of Semu's men (Iben and Hetsut) ambush the doctor, murder him, and steal Klaris the mummy. The medallion is left behind because the attackers couldn't find it, setting up the scenario where Abbott and Costello stumble upon it.

At the Cairo Café, a waiter warns them that the medallion is cursed. During the frantic scramble to finalize the exchange between Abbott and Rontru, the medallion accidentally falls into Costello's hamburger, and he eats it without realizing what happened.

Rontru takes Abbott and Costello to a doctor's office to view the medallion under a fluoroscope, hoping to decipher its markings. However, the inscriptions are carved in ancient hieroglyphics that resist modern interpretation, so the meaning remains unclear despite the medical imaging.

Semu, the leader of Klaris's followers, reappears posing as an archaeologist who offers to guide the group to the tomb. This is a deception to get close to the treasure and eliminate the others. While Semu is convincing the group to follow him, his actual followers have already revived Klaris, turning the expedition into a much darker pursuit.

Once the group reaches the tomb, Costello discovers that Semu plans to kill them all to secure the treasure for himself. Semu's murderous intentions become clear when he reveals his true colors, setting up the climactic confrontation in the temple.

After Rontru captures Semu, Charlie (one of Rontru's men) disguises himself as a mummy to enter the temple. Abbott also dons a mummy disguise, and the two work together to rescue Semu from danger inside the temple complex.

In the climactic temple scene, Rontru uses dynamite to blast through to the treasure. However, the explosion goes wrong, it kills Klaris the mummy but also destroys the obstacles protecting the treasure, finally revealing the hidden wealth.

After the treasure is revealed, Abbott and Costello persuade Semu to preserve Klaris's legend rather than loot the tomb for profit. They convince him to transform the temple into a nightclub, ensuring the story of Klaris endures in a playful, lasting way while leaving the treasure untouched.

When Rontru offers Abbott and Costello $100 for the medallion, Abbott suspects its true value is much higher because of its connection to the legendary treasure of Klaris. He counters with a demand for $5,000, which Rontru agrees to pay, indicating she understands the medallion's true significance.