A series that was on in the late '70s that was set in a kind of ancient Inca civilisation in Aztec Mexico and starring former Doctor Who Patrick Troughton as the scheming High Priest Nasca.
Two series were made for ITV by Thames Television and transmitted in 1976 and 1978. It was on during childrens TV schedules, although much of it was creepy and menacing and wouldn't have been suitable for very small kids. Opening shots showed images of Aztec-type gods looming up to the accompaniment of groaning, wailing sounds; I recall that the series featured a mad priest who thought he was a god called Tescata, he ended up being walled up alive in a series of tunnels underneath the city....Ring any bells??