(William Hartnell) emerges, Achilles believes him to be Zeus in disguise, and brings him to the Greek encampment along with the warrior Odysseus (Ivor Salter). Greek leader Agamemnon (Francis de Wolff) insists the Doctor help them fight the Trojans. Meanwhile, the Doctor's companions Vicki (Maureen O'Brien) and Steven (Peter Purves) remain in the TARDIS. Steven goes alone to try to find the Doctor, but is captured by Odysseus and taken to the Greek camp. Pretending to be Zeus, the Doctor persuades the Greeks to spare Steven. Priam's son Paris (Barrie Ingham) takes the TARDIS into Troy. Priam's daughter, the prophet Cassandra (Frances White), denounces it as dangerous and demands it be burnt. Before the fire is lit, Vicki emerges from the TARDIS, taken as a sign from the gods. She is renamed Cressida and made a court favourite, enraging Cassandra, who believes Vicki to be a rival prophet, though her handmaiden Katarina (Adrienne Hill) defends Vicki. Priam sends Paris out to avenge Hector, but Steven adopts the identity Diomedes and persuades the Greeks to send him instead, hoping to search for Vicki. When he arrives, Vicki greets him with his real name, which Cassandra sees as a sign they are both spies; they are taken to cells. Priam's youngest son Troilus (James Lynn) visits Vicki. She persuades him to try to get them released, and they begin to fall in love. Priam has Vicki released, and she frees Steven. Troilus kills Achilles to avenge Hector. At the Doctor's proposal, the Greeks pretend to sail away, leaving a wooden horse outside Troy as acknowledgement of defeat. Paris brings the horse into the city. At nightfall, the Greeks and the Doctor exit the horse and open the city gates, allowing the Greek army to enter and battle. As the fighting rages, the Doctor finds Vicki. Priam and Paris are slain, and Cassandra taken prisoner. Katarina finds Steven badly wounded and helps him return to the TARDIS. Vicki leaves the Doctor, anxious to find Troilus; outside the doomed city, they declare their love for each other and flee. The Doctor dematerialises the TARDIS with Steven and Katarina on board, hoping to land somewhere to attend to Steven's injuries. Production Conception and writing After assuming the position of story editor in April 1965, Donald Tosh wanted to take Doctor Who in new directions, such as experimenting with humour and horror in historical episodes. Tosh