Things become very exciting in the storyline as writers begin to ease into their role and viewers fanatically tune in each week.
The Thals are convinced by the time travellers that violence can be used for good and it is decided that the tribe will attempt to overthrow the Daleks. One group of the Thals lead Ian and Barbara through the swamp at the edge of the Dalek city with the intention that they will gain entrance unseen and be able to gain access to key areas of the Dalek Empire. Viewers are treated with the newest technology in special effects where the radioactive lake, filled with unseen, but apparently horrifying mutants splash and threaten anyone who tries to come near. Barbara and ian spot a multi tentacle creature in the water and unconvincingly show thier horror and fear at what else may lurk underneath the waterline.
Another group of Thals, lead by the Doctor and Susan plan to act as a decoy by entering the front gateway.
The Daleks have very primitive scanning technology and are able to see the tries huddling together and planning things, but they are unable to hear what is going on. The Daleks are further distracted as they discover that the anti radiation medicine they had taken from the Thals has devastating side effects. They decide to increase the radiation output across the planet by setting off a huge bomb; which they believe will wipe out the Thals entirely.
Viewers are left with a scene where Ian has just discovered a number of pipes leading from the lake into the city. One of the tribe members screams as a mutated monster drags him under the water and into a whirlpool.