The year: 2020. The Terrahawks Organisation is mounted and they are ready to defend Earth against hostilities. When an energy source is picked up heading for Earth Lt Hiro and his robot Zeroids blast off - but fail to destroy it.

The Hawkwing and Battlehawk are launched to investigate, but Ninestein is captured by Zelda, who uses him as a hostage in a bid to escape - but Hiro frees Tiger.

When Zelda releases one of her allies, Lord Sram, from suspended animation and sends him to Earth, Sram is shot down by Kate Kestrel. But the alien survives the crash - and makes life very uncomfortable for Tiger Ninestein.

Master of disguise, Mold, a faceless alien, is sent to Earth by Zelda. He crash-lands in the Arctic in the form of Lt. Hiro, to sabotage Earth's defences and allows Zelda to invade the planet.

When Spacehawk picks up an unmanned and unharmed space capsule and finds it contains Yuri, a cuddly space bear, Mary Falconer and Kate Kestrel adopt Yuri as their pet - but the bear is really Zelda's agent.

Journalist Mark Darrol threatens to expose the Terrahawks. Zelda contacts him and puts him aboard a ship taking food to the Terrahawks' base. But Tiger Ninestein has his own methods of writing off this latest threat.