It was Independence Day 1990. Don Pancho (Guillermo) Wiese and archaeologist Dr. Régulo Franco, were heading towards Huaca Prieta, where Junius Bird had discovered the first traces of sedentary life in ancient Peru in 1946. A settler from Magdalena de Cao, Arturo Carrera —nowadays an expert craftsman—, told them he had heard rumors of painted friezes in Huaca Blanca (Huaca Cao), one of the shapeless mounds in the area. The next day, Don Pancho and Régulo Franco crossed a desolate landscape until they reached the huaca: the ground was full of holes due to the clandestine diggings, there were fragments of pottery, textiles, and metallic pieces scattered everywhere. When they reached the site, Arturo Carrera showed them what he had cleaned that very morning for them: a colored frieze in relief depicting two characters pulling a chinchorro, a fishing net which is still in use today by fishermen in the Chicama valley.

This finding, the first multicolored Mochica frieze in a big pyramid —now known as the Complex Theme— was enough for Don Pancho and Régulo Franco to focus entirely to researching the area. In August 1990, as soon as the excavations began in the north face of the pyramid, they found a disturbing yet fascinating image on a wall: the hand of a character holding a ceremonial knife, or tumi, and with legs of a sea arachnid was displayed. Don Pancho, Régulo Franco and their enthusiastic assistants, kept on clearing and revealing the rest of the character, which later turn into the leading star for Don Pancho Wiese. In fact, the Arachnid Decapitator was the spark which forever lit the research enthusiasm of these men, who worked tirelessly for years in order to reveal the complex puzzle of Huaca Cao, and which led to amazing discoveries that shed light on the development of the civilization in the northern coast.

Huaca Cao had been overlooked by foreign researchers, who thought it was a Chimú building. A cross section in the south face, apparently made during the Colonial times, was reported in the 1930s by Kroeber and Ubbeloh-Döringer; other evidence was published by Rafael Larco Hoyle in 1948. However, until the research begun by Don Pancho Wiese and Régulo Franco nobody suspected the magnitude of this archaeological site.

The sustained work of the Archaeological Project of El Brujo, led by the Wiese Foundation, has revealed this important site, which has been continuously inhabited for thousands of years. The hunter-gatherers who found sustenance in this area around 10500 B.C. gave way to the first settlers in 4000 B.C., and later to the Cupisnique, with their monumental buildings, their sophisticated works in gold, stone, pottery, bone and snail shells. They were followed by the Gallinazo and the Salinar, and later by the most important culture in the history of the site of El Brujo: the Mochicas, whose great hydraulic knowledge inherited from the Cupisnique allowed them to develop a complex society, and whose art has remained forever captured in their pottery, metallurgy, textiles and a richly decorated architecture. The Mochicas yielded their reigns to the expansion of the Chimor kingdom, which in turn were subdued by the Inca Empire. Even the Spanish occupation is registered in the site, as it keeps the remains of a Colonial village and a church.

Thanks to the research work of the experts summoned by the Wiese Foundation for 20 years, the history told by the site of El Brujo has reached the eyes and ears of the whole world. The findings have been shown in international publications and since 2006 Huaca Cao is open to the public. Soon, visitors of the Cao Museum will be able to immerse themselves even further in the fascinating world of the ancient dwellers of the Chicama valley.