The Doctor and Jo evade the maggots and mount an old mine car on the tracks.
Jones and the Brigadier are now convinced the Global Chemicals is responsible for the deaths.
The Doctor and Jo punt the mining car across the green slime.
Elgin confronts Fell, who is robotic and unconcerned about the mine.
The Doctor and Jo make their way to safety and ascend a crevice in the Earth.
The Brigadier confronts Stevens about the deaths. Stevens threatens the Brigadier with his friends in high places and calls the Minister of Ecology.
The Doctor finds a cache of massive green eggs and takes one for examination.
Elgin finds Fell running pumps, emptying a chemical tank. Fell is evasive about his actions.
The Minister of Ecology tells the Brigadier to cease his investigation. When he refuses, the phone is handed to the Prime Minister, who orders to Brigadier to help Global Chemicals.
The Doctor and Jo finally reach a pipe connected to Global Chemicals. When they climb, they set off an alarm in the pump room. Fell prepares to pump waste into the pipe anyway. Elgin tries to open the pipe as Fell grows more confused. Fell finally helps him just in time to save the Doctor and Jo from being killed by a flood of green slime.
Stevens agrees to give UNIT an office in his factory.
The Doctor quickly explains what they've found to Elgin. Elgin promises to help.
Fell staggers into Stevens' office and Stevens puts a headset on him. Fell realizes that something has been done to his mind. The Boss tells Stevens to destroy Fell. Fell leaves, rushes past the Doctor and jumps over a balcony to his death. Stevens, shaken by the event, is taunted by the Boss.
At the Nuthatch, the UNIT people have dinner with the scientists. Cliff tells the enthralled Jo of his plans to go to the Amazon to look for a legendary fungus that could replace meat. They then find out that Bert has died from the green slime.
Stevens, hearing about the green egg, sends Hinks to steal it back.
Jones comforts Jo over Bert's death. They are about to kiss when they are interrupted by the Doctor.
As the Doctor talks to Cliff, Jo begins to read a book on the Amazon. As she does, the egg shatters and a green maggot emerges. It slithers hungrily around the Nuthatch until it sees Jo. It quietly advances on her…