Chocky hopes, with Matthew and Albertine's help, to help the human race discover cosmic power, which unlike Earth's finite natural resources, will sustain them for as long as the universe itself exists. But their knowledge has aroused a great deal of interest from the military, and they are willing to take drastic action if they don't get what they want.

• Thames Television
• Prentis Hancock
• Anabel Worrell
• Illona Linthwaite
• Joan Blackham
• Glynis Brooks
• Paul Russell
• Freddie Brooks
• Karina Wilsher