Commander Azaxyr and his Ice Warriors are revealed as traitors, in league with Galaxy 5.
Sarah is distraught at the Doctor’s apparent death. Azaxyr orders Eckersley to return the temperature to normal and turn off the ventilation in the mines.
The Doctor, having survived the blast, returns to the mines. Gebek informs him that the Ice Warriors will soon be entering the mine and that the air is getting stale. The Doctor heads for the refinery, where the ventilation controls are. Gebek also informs the Doctor that Sarah is no longer in the mines.
Alpha Centauri informs Thalira, Ortron and Sarah that Azaxyr has imposed martial law on Peladon; Thalira will rule in name only. They plan their escape. They distract Sskel, and he is too slow to chase them. However, Ortron is killed while trying to protect his Queen, and Azaxyr returns in time to stop Thalira from escaping.
The Doctor and Gebek reach the refinery. Inside the refinery, Azaxyr and Eckersley gloat that their plans are working. Sarah and Alpha Centauri are in the communication room, where Alpha Centauri sends a general distress signal. Sarah discovers that Eckersley is really in league with the Ice Warriors. Eckersley sends out the Aggador apparition – a matter projection of a statue of the Royal Beast armed with a directional heat ray – to scare first the miners, then the Pel guards. Sarah, on discovering the Doctor is alive, runs to join him, leaving Alpha Centauri on its own in the communications room.
Eckersley and Azaxyr head back to the citadel, leaving a guard behind. Sarah appears, which distracts the guard long enough for the Doctor and Gebek to dispatch him. Azaxyr and Eckersley return to the communications room, and Azaxyr realises Alpha Centauri sent a distress call; he sends it to the throne room.
Alpha Centauri tells Thalira that Azaxyr and Eckersley are really working for the Federation’s enemy, Galaxy 5. Alpha Centauri accidentally gives away that Sarah is on the loose, and is forced under threat of death to tell Azaxyr that Sarah and the Doctor are at the refinery. Azaxyr sends Sskel to the refinery; when he reaches it, the Doctor, Gebek and Sarah are already inside. He begins to blast the door. Other Ice Warriors join him while the Doctor works furiously at the controls.