News that the Earth has been visited by extra-terrestrials sends the world's press into a meltdown. Peter goes on an unexpected journey.

Professor Mayer and his son Edward return to Sydney, pursued by the opportunistic American businessman Rudolph Lindenberger.

Jean, Bernie, Edward and Professor Mayer are spirited out of Sydney to the Parkes radio telescope. Still stranded on Soshuniss, Peter is forced to deliver an ultimatum to the Australian Prime Minister.

Peter's return to Earth sends Parliament House into a panic. Still on the run, Adam attempts to contact Jean and Bernie. Meanwhile, Lindenberger's men close in.

The arrival of Lindenberger's henchmen leads to a dramatic chase across the Parkes radio telescope dish for possession of Adam's radio. With Soshuniss under threat by Earth, Professor Mayer volunteers as a human shield.

Threats of attack by Earth lead the Soshunites to announce they will only negotiate with the children. The Australian Prime Minister outsmarts Lindenberger. (Final)