The TARDIS lands in the middle of the Trojan War, where the Doctor is mistaken for the god Zeus.

While Odysseus forces the Doctor to find a way to win the war, Steven decides to get himself taken prisoner in order to enter Troy and find Vicki and the TARDIS.

With Steven and Vicki being held prisoner by the Trojans, the Doctor's only hope of seeing them again is to suggest the idea of the Trojan Horse.

The Doctor waits inside the Trojan Horse for a chance to reach his companions but Steven's assumed identity as a Greek soldier and Vicki's growing feelings for Troilus endanger their escape.