He adds: "This Aztec moment was an astonishing moment, both historically and culturally. One of the great archaeological events since the Second World War has been the discovery of the Templo Major" (the great Aztec temple) in the centre of Mexico. It's as if we were able in London to unearth some great Roman mega-site under St. Paul's Cathedral. It's a fantastic event."

However, this is the RA, not the British Museum. One of the curators, Dr Adrian Locke, says: "I see this as being much more of an art-based show than an archaeological show. We are trying to present a glimpse of the Aztecs as a civilisation through their art. We're going to try to give people a sense of what the Aztec empire was all about - give a sense of the kind of art they produced, the kind of society they lived in. We're looking at the most ornate objects, the most beautiful, the most refined. They're clearly objects that are meant for public veneration, or veneration by the elite members of Aztec society."

Rosenthal is convinced that those objects have an amazing power after all this time. "The Aztecs are a thing in people's imagination. The word is one of those spine-tingling ones, a bit like Pompeii. They send a shiver down people's spines. And we have these incredible lifesize figures - the Eagle Warrior, and the god of the underworld, the first time he's been seen outside Mexico. It's incredibly generous of Mexico to allow these amazing, delicate objects to come to London."