The Aztecs DVD signed by William Russell
The TARDIS crew arrive in Mexico in the 15th Century. With the TARDIS trapped in a tomb, Barbara is mistaken for a female reincarnation of the ancient high priest Yetaxa, and assumes her guise and identity. From her new position of power, Barbara sees her chance to bring an end to human sacrifice. She sees the good side of Aztec culture manifested in Autloc, the High Priest of Knowledge, and the gruesome side embodied in 'the local butcher', the High Priest of Sacrifice, Tlotoxl. As something of an expert on this period, she sees how advanced their culture really is and believes that if sacrifice were abolished, they would be spared destruction at the hands of the Spanish. The Doctor's urgent warnings that Barbara cannot change history fall on deaf ears, much to the Doctor's fury.
The bloodthirsty Tlotoxl begins to suspect Barbara is not Yetaxa returned, especially because she is trying to ban human sacrifice. He sets a series of elaborate traps for her and her companions. For example, Ian has been compelled into the military and fights the strongest warrior, Ixta, to prove his ability to command the Aztec forces. Thus Ixta develops a grudge against Ian and is used by Tlotoxl to try to prove that Barbara is not Yetaxa. The Doctor unwittingly tells Ixta how to defeat Ian in combat using a drugging agent, and this battle nearly ends in the Doctor witnessing his friend's death. When this fails to be conclusive, Tlotoxl convinces the subordinate priest Tonila to make a poison for Barbara; the death of Barbara following consumption of the poison would prove she is not immortal and therefore not a god. But Ian silently warns her from his hiding place, and Barbara refuses to drink the poison. She tells Tlotoxl that she is not Yetaxa but warns him not to tell the people. He now knows the truth - but must find a way to unmask the false goddess.