3rd January – 24th January 1981
You were the noblest Romana of them all.
The Doctor to Romana, episode 4
Still trapped in E-Space, the TARDIS is boarded and hijacked by Biroc (David Weston), a lion-faced time-sensitive Tharil, who then promptly vanishes into the mists of the eerie void into which he has steered the ship.
The Tharils, once rulers of a vast empire and notorious slave owners, are now slaves themselves, many of them held captive aboard a Privateer ship, crewed by a gang of slavers under Captain Rorvik (Clifford Rose). The Privateer is also trapped in E-Space, unable to navigate without its recently escaped time-sensitive, Biroc.
The Tharils’ downfall came about at a feast a long time ago. Their own slaves engineered warrior robots, Gundans, which slaughtered and wounded their masters at the height of the feast. Usually capable of passing through any substance the Tharils were unable to evade their Gundan attackers, nor the later chains that bound them into captivity because both were forged of dwarf-star alloy, the only metal they cannot pass through.
The Doctor follows Biroc into the mist, passing underneath the Gateway, a crumbling stone edifice that leads into the ruined banqueting hall, where Gundans still guard the remains of the great feast. But Biroc has disappeared, his footsteps stopping dead in front of a huge wall mirror.
Romana is anxious to find some spare parts for K-9, badly damaged during Biroc’s piloting of the ship into this hub between E-Space and normal space. Hopes that Rorvik’s ship might prove a useful source are dashed when the slavers decide she would make an acceptable substitute time/space navigator.
As Romana fights to free herself, the Doctor enables a Gundan to talk and reveal the secret of the Gateway. Once it was a mighty castle, standing at the zero point between positive and negative space coordinates, until the Gundans were built. Rorvik’s arrival interrupts the story, but as he tries to get away the Doctor stumbles against the mirror and passes through … into the past of the Tharils, and to the night of their downfall at the feast.
Biroc re-appears, crossing effortlessly between the time lines. He advises the Doctor to do nothing to prevent Rorvik’s scheme to blast his ship free from the Gateway using a blast from its main engines. Sure enough, the blast reflects off the mirror, shattering the dwarf-star metal of the ship, killing the crew but releasing the slaves.
Not wanting to go back to Gallifrey, Romana chooses to stay in E-space with K-9 and help free more Tharil slaves. The Doctor has no time to argue: the TARDIS will be able to ride the energy from the exploding Privateer and knock itself back into normal space.