There is to be a sacrifice in three days time and Barbara is determined to stop it. Ian recovers from the drug Ixta administered during their fight and finds him somewhat more conciliatory. In trying to gain Cameca's support, the Doctor finds that he has inadvertently become engaged to her. He may have found a way into the tomb however. Tlotoxl is determined to prove Barbara is a false god and tries to poison her. When that fails, he focuses on Susan, who is reluctant to accept some Aztec practices. When she refuses to marry the man chosen for her, Tlotoxl arranges for her to be publicly punished.
—garykmcd