The Governor and Chief Office interrogate Peri but get into an argument over the mining.
The Doctor's body is moved for disposal in acid. He revives just before the guards can destroy his body. They try to throw him in but fall into the acid bath instead. He slips away but is quickly caught by Quillam.
Peri tries to tell the Governor and Sil where she came from but they don't believe her. The Chief Officer suggests turning her over to Quillam.
When the Governor hears that the Doctor has been captured, he decides to hang the Doctor and Jondar. The Doctor plays along until they are in the nooses, when he tells them that Zeiton-7 holds the key to their future. Sil, enraged, has his guards pull the lever. The Doctor and Jondar fall harmlessly, the nooses having not been connected. The Governor was trying to scare a confession from them.
The Governor wants to hear what the Doctor has to say, but the Doctor demands that Peri and Areta be freed from the transmogrification chamber. Sil, enraged, withdraws his offer for Zeiton, inadvertantly releasing the governor from the binding vote.
Peri and Areta begin to change into animals. The Governor demands that Quillam stop the experiment but he refuses. The Doctor rips Quillam's mask off, revealing his hideously transmogrified face. The shock allows Jondar and the Doctor to get the guns off the guards. The Doctor blasts the control panel, stopping the experiment and throwing the Dome into chaos. They race to Peri and Areta, who slowly change back to normal.
They try to escape in the damaged Dome but the confused Peri wanders off and is caught. The Chief Officer brings her back and demands a final vote on the Governor for failing to surpress the rebellion. The Governor explains to Peri that once he is dead, the next Governor will be selected by random ballot. He tries to appeal to Maldak to let them go but the officer refuses to listen.
The Doctor, Areta and Jondal reach the End Game, the supposed way out of the Dome. They see visions drawing them forward but the Doctor sees through them just before they step into a pite of acid.
The Governor calls for the vote and it goes against him (Arak hitting both his and Etta's buttons). The radiation beams pour down even as he tries to appeal to Maldak. The officer finally gives in and blasts the radiation beam, setting the Governor free. He leads them into the ventilation ducts to find the Doctor.
The Doctor's friends are next attacked by cannibals. They run to a garden but the Doctor warns them not to touch the dangling tendrils. When one cannibal does, he is instantly poisoned. The hear the Chief Officer and Quillam approaching and the Doctor has Jondal set a trap using the tendrils. Quillam sends his men to brutally torture them. But the Doctor sets the tendrils free, killing the officers. They are then joined by Maldak, Peri and the Governor.
Sil contacts the invasion fleet and hears that the fleet is on its way from Thoros Beta. When the Governor returns, he gloats over the pending invasion. But a message comes in explaining another Zeiton source has been found and the invasion cancelled. With the critical need for Zeition, Sil is instructed to pay any price. The Governor immediately triples his opening bid.
Promised all the Zeiton-7 they want, the Doctor and Peri leave Sil, who flies into such a rage he blows out his translation module.
The Governor makes one last broadcast, explaining the situation to the Varosians. Now that they are free, Arak and Etta have no idea what to expect…