When he and his companions returned to Kylon, the Doctor managed to get the TARDIS to materialise right in the middle of the Last City's central square. The scanner screen showed groups of Kylonians going about their business, apparently too preoccupied with their own affairs to bother about the TARDIS, although a few did cast curious glances in the direction of the strange blue box which had materialised in their midst.
The Doctor switched off the scanner and turned to Tegan. "Right, we're there," he told her. "Get Nyssa and Adric, will you?"
"Right." Tegan hurried off to the laboratory, where Nyssa and Adric had been processing the sylium the TARDIS crew had collected on Nava V. Their visit to the small planet had, for once, been uneventful, aside from the time Adric, in a moment of inattention, missed his footing and ended up dangling over the edge of a cliff. The Doctor had had to pull the boy to safety. Afterwards, he had given Adric a scolding for not watching where he was going, to which Adric had responded with his usual complaints about being treated like a child. Luckily, Nyssa had intervened before another shouting match could erupt between the two male humanoids. Tegan smiled at the memory as she returned to the Console Room with Nyssa and Adric following her, each of them carrying a bag containing the sylium Nyssa and Adric had been processing.
"This stuff is heavy," Adric muttered as the three of them entered the Console Room.
"This "stuff", as you call it, saved your life," Tegan reminded him, privately adding that he was right about it being heavy. Finding the small amount of sylium needed to revive Adric was one thing, but they needed much more than that if they were to rid Kylon of the Jara Pods.
Adric looked as though he was about to say something in reply, but, before he could do so, the Doctor opened the doors to the TARDIS and told his companions to follow him. Several Kylonians stared in amazement at the sight of four people, three of them carrying large transparent bags, emerging from the blue box. But the Doctor was used to this kind of reaction and told his companions to ignore the stares and follow him.
They met two Scouts outside Kerez's house: Idral and a female Scout whose name they did not know. The second she saw them, she held up her hand to block their way, prompting a sigh of exasperation from the Doctor. He had hoped they would meet Marena, but she was clearly not available at present.
"It's all right," Idral told his companion. "I know these people; they were here six months ago."
"Six months?" Tegan echoed, turning to the Doctor.
"Yes, well I wanted to be sure the Jara Pods would be dormant when we returned," he told her. To that end, he had programmed the TARDIS to return to Kylon a few months after he and his companions left for Nava V; he had studied Jara's notes extensively and knew the pods were only dangerous when they were spreading their spores. Then, drawing himself up to his full height, he turned to the two Scouts. "Take us to Kerez," he said, his tone, though mild-mannered, making it clear that they had better do as he said.
Within minutes, the Doctor and his companions were standing before Kerez, showing him the contents of the bags. "Sylium," the Doctor explained, holding up a small amount of the chalky mineral. Then, seeing the puzzled look on Kerez's face, he hurried on. "It's the same stuff that was in the antidote we gave to Adric." He gestured towards the boy, who was standing with Tegan and Nyssa, looking somewhat bored with all the talk that was currently going on. Kerez looked from the Doctor to Adric, then back again, recalling the events of six months earlier and wondering why the Doctor had returned with more sylium when it wasn't needed any more. He put this question to the Doctor, who responded by handing him Jara's notebook.
"The answer's in there if you'd care to read it," he said, hoping Kerez was prepared to accept help with getting rid of the Jara Pods. The Doctor may have had a habit of becoming involved in the affairs of other planets, but he knew not to push it too far. Still, Kerez had lost his son because of the pods and their spores and had seen another boy come close to suffering the same fate, which meant he should be keen to see the pods destroyed.
After a brief discussion, Kerez agreed to accept the Doctor's offer of help. The Jara Pods had long been a menace to the people of the Last City, so maybe it was time they were rid of them once and for all. And the only way they could do that was to use the sylium the Doctor and his companions had brought back with them. "Very well, Doctor," he said. "Leave the sylium with me and I'll have some of my Scouts use it on the pods." After that, no-one would ever have to worry about inhaling the deadly spores again.
"By the way," the Doctor said next, "how's Talda?"
"She's fine," Kerez replied. "I've adopted her and Marena's training her to become a Scout." As for the rest of the Bandits, he went on to explain that they had dispersed after the death of their leader, leaving the abandoned laboratory which had been their den deserted. The people of the Last City had no use for any of the equipment; they were keen not to repeat the mistakes of their ancestors. So they had left everything where it was and barred the entrance to keep anyone from entering.
The Doctor was tempted to argue that science, when used for the right reasons, could be beneficial. But he chose not to, deciding that, if the Kylonians were content to live in a Level Two civilization, they were welcome to do so. Instead, he turned to Tegan. "Ready to go?" he asked her. "Heathrow Airport, 1981. We'll be watching your flight take off," he added, nodding towards Nyssa and Adric. Visiting a busy airport should be quite an experience for both of them . . . He only hoped Adric's curiosity wouldn't get the better of him.
"Actually," Tegan said, remembering the decision she had made while she and the Doctor were prisoners in Gark's territory, "I'd like to stay with you for a while."
The Doctor looked at her, surprised to hear her say those words after the amount of time she had spent nagging him to get her back to Heathrow. Still, if she wanted to stay in the TARDIS a little longer, that was her business; besides, the airport would still be there if she ever changed her mind again. Then, with nothing else to do on Kylon, he and his companions took their leave of Kerez, before heading back to the TARDIS and more adventures.