The Oxaqua Incident

The Oxaqua Incident was the 4th episode of Season 21. It featured the Fifth Doctor, Tegan and Turlough.

Plot
The Doctor has taken Tegan and Turlough with him to Oxaqua to get some Rellium crystals for an experiment he is working on. While he is there he becomes embroiled in a water dispute between the two sentient species. The humanoid Basks are building dams which take water from the Theigs (a bizarre looking race with squat bodies, conical heads and eyeballs that writhe around on long tendrils). Matters have come to a head and Ghum, one of the Theigs, is threatening to blow up the outlet from one of the energy collectors attached to the planet's core. Lava will engulf the city. The Doctor follows Obedee, leader of the Basks, to the scene and talks Ghum out of blowing the place up in exchange for mediation.

The Doctor offers to arbitrate, but Obedee abruptly has Ghum arrested, along with the Doctor and his companions. They are all sentenced to death and taken to a room where they are tied to a slab. A rock with metal spikes is suspended above them, ready to drop. Before that can happen, a Theig attack blows the walls and the prisoners are freed.

They are chased across the city and hide in a house which is demolished by a Bask ray. They find themselves in the cellar and Ghum uses his conical head to burrow out into the next cellar. The four of them flee into the desert. Ghum tells the other three to go on without him - he has a plan.

The Doctor and his friends are soon overtaken by Obedee and his men. Before the Basks can issue any punishment, tiny tornados sweep across the desert. They are a product of the Basks' damming of the water. Obedee is caught in one, the skin flayed from his body. As the tornados surround the others they are saved by a sudden inrush of water. Ghum has blown up one of the dams.

The Theigs and the Basks are reconciled and the Doctor is given his Rellium crystals. He is also awarded a replica of the Oxaquan sword of Office. He leads his friends back to the TARDIS and they leave. The Doctor tells them that the people of Capu 2 would say "Skirri bip hoom da lunce" at this point. Tegan asks him what this means but he says that he has no idea; he just knows that they always say that on Capu 2.

Continuity
to be added