When the Doctor finds out that a Warrior was headed for the station, he follows. There, the Doctor creates a solar energy transmitter to destroy the creature. He then repairs the controls so that rain can be created. With the satellite in space the Doctor returns to the Moon to put Slaar's own signal out of action. Whilst tampering with the device he is captured by Slaar.
Contact is lost as the entire fleet is destroyed.
Slaar orders the Doctor to be killed but Jamie arrives via T-Mat at that moment and the Doctor uses the confusion to grab the Warrior's gun arm and point it at Slaar who is killed. The Doctor then electrocutes the remaining Warrior. As rain falls across Earth, Kelly and Eldred argue about the future use of rockets and T-Mat. The opening titles were backdropped with a scene of the Earth and Moon. Patrick Troughton does not appear in episode four as he was on holiday during its filming.