BERLIN: An ancient artifact lost in the chaos of World War II. An American scientist hunting for Nazi secret weapons. An archaeologist who dug into dusty archives to prove a hunch.

What sounds like the plot of an Indiana Jones movie is turning into a happy end for a German museum that feared it had lost a treasured stone tablet from ancient Egypt.

The tale begins more than 3,000 years ago during the reign of Ramesses II, when Ptahmose, mayor of the Egyptian city of Memphis, had his portrait chiseled onto a stele.

Unusually, the stone slab was glazed, helping preserve the image of Ptahmose with his arms raised in worship of the ancient Egyptian deities Osiris and Isis.

The National Museums in Berlin purchased a fragment of the slab from an English collection in 1910. It was displayed in the German capital until WWII, when the museums were shut and large parts of the collection moved to safety due to aerial bombardment.

The stele was left behind and recorded missing, assumed destroyed, after the war.

The Prussian Cultural Heritage Foundation, which oversees the museums, said Tuesday that the artifact was rediscovered by a Dutch Egyptologist, Nico Staring, in the collection of the Kelsey Museum of Archaeology at the University of Michigan in Ann Arbor.

Research showed a Dutch-American scientist, Samuel Abraham Goudsmit, had purchased the stele in 1945 from a private collector in Germany and bequeathed it to the Michigan museum, the foundation said.

Goudsmit was the scientific head of a secret US army mission investigating Nazi Germany's efforts to build a nuclear bomb, as well as an enthusiastic amateur archaeologist.

The Kelsey Museum agreed to return the stele, which will be displayed in Berlin from next month.

Hermann Parzinger, president of the Prussian Cultural Heritage Foundation, called the return of the stele a "noble gesture."

"Now, after more than 70 years, it will once again take its place in the permanent exhibition of the Egyptian Museum of Berlin," he said