Whilst Starkey and Jorjie are trying to escape the police, they take refuge in a large detached house, now the residence of reclusive scientist, Professor Gryffen. They come across two Jixen warriors and a robot dog, K-9 Mark I. After the ensuing battle with the Jixen, K-9 regenerates...

Having been "tagged" by Jixen slime, Starkey is in hiding from The Department and from the Jixen warrior who survived K9’s blast. Jorjie tells Starkey that the Department is imprisoning Aliens, and K9 flies off to investigate. Jorjies’s mother turns out to be Department inspector June Turner, and there is a confrontation as the youngsters and K9 try to help release the innocent Aliens. Starkey confronts the Jixen with dire consequences.

Starkey is homeless and K9 and Jorjie try to help. Gryffen’s assistant Darius contacts them after the Professor, an agoraphobic, disappears from the mansion. A warning from the 50th century is received, and K9 and the youngsters give chase to a mind-sucking alien called the Korven, who has snatched Gryffen.

K9 becomes confused about his memory loss when an alien "bounty hunter" arrives and teams up with an evil Department inspector called Drake. Ahab, the Bounty Hunter, claims there is a price on K9’s head for murdering a galactic peace delegate in the 50th century.

Drake uses a strange alien substance on a group of school children in an experiment to gain control of the population. Jorjie stumbles across the plan, and K9 and Starkey have to find and destroy the control devices.

London is out of control; riots erupt due to irrational fear. The focus of the paranoia is based in an old junkyard where a strange alien consciousness is at work. K9 discovers the emotion of fear for himself in his bid to thwart the unknown.

Darius, Starkey and Jorjie spend a very spooky evening at Gryffen’s mansion, as spectres from Gryffen’s past materialise, causing mayhem. K9 sees the "ghosts" for what they really are, and the group have to convince Gryffen before the youngsters' life forces are drained away so that the alien energy beings can take physical form.

Inspector Drake is attacked by K9, or so it seems. June Turner and the Department have orders to capture K9 and destroy him. However, Starkey discovers Drake has had a basic double of K9 built to discredit him.

An ancient stone obelisk is unearthed by the Department, and an alien force is unleashed that literally starts inducing everyone to sleep and dream. The Bodach feed on brain waves, and what better entrees than human nightmares?

K9 meets the Anubians, a race he helped in his long-forgotten past. Once placid, these creatures have now become warmongers. They trick K9 by worshipping him as their saviour, a veritable God. Darius sees through the plan and tries to thwart the alien invasion.

K9 notices a change of behaviour within his group of friends and discovers that time itself is being disrupted. Small chunks of time are being "eaten away". A "Time Snake" has invaded, and Starkey makes a discovery that means that only he alone can face the Oroborus and offer himself up as a meal to defeat the creature.

Following The Thames being heavily polluted by an alien chemical, K9 discovers the alien "Medes" are imprisoned by Drake and they need a special "key" to be made for the release of their spaceship.

London is being bombarded by strange sound waves that cause mass panic. K9 and Starkey are on the trail of the Alien, identified by Gryffen as an Aeolian. Darius desperately tries to rescue Jorjie as she is trapped by falling debris.

Panic ensues when a museum exhibit is stolen and K9, Starkey, Darius and Jorjie are on the trail of the culprit only to find a giant menace hiding in London’s abandoned sewers. However, is the Alien really a threat or is Drake the bigger evil?

The Department are using an experimental device that literally eats rubbish. Darius sees an opportunity to make some money and snatches the device. However, the alien virus in the device escapes and threatens to devour everything it touches.

A freak accident engages the STM, and Jorjie is taken back in time to 23 November 1963. K9 and Starkey follow to rescue her and become embroiled in a spy-ring and a race against time to save Darius from never having existed.

Inspector Thorne sets a trap for K9 and Starkey is whisked away to a far-off planet all contained within an alien library card. The Librarian arrives to reclaim the card, and K9 and friends need June’s help to rescue Starkey and teach Thorne a lesson.

The CCPC’s are hunting a rogue officer who has developed a personality and consciousness. K9, Starkey and Jorjie take the rogue CCPC back to Gryffen’s mansion and hide him from The Department, only to face the mutant copper causing mayhem.

"Little Green Men" is a new virtual reality game that is sweeping the nation. However, it has a hidden secret. It has a link to an Alien that turns humans into his own kind. K9 and Starkey race to save Darius and Jorjie from being turned into scaly green creatures.

Gryffen tries to free a time being imprisoned by The Department. He was responsible for an experiment that bought the "Time Blank" into being and K9 assists him in his plan. Unfortunately, the Blank, in the guise of a girl (Taphony), turns on Gryffen and begins to drain Jorjie's life force in an attempt to stabilise her existence. Guest stars Maia Mitchell as Taphony.

Darius and K9 go undercover to expose a criminal who is using illegal robot technology in what he calls "destruct-ertainment". K9 becomes a Gladiator and has to face the evil "pain-maker" in a battle to the death. But what is the sinister secret plan instigated by Thorne?

K9 is using the STM to try and rectify his memory loss of events prior to his arrival and regeneration. Gryffen and Starkey discover him linked to the machine, which creates a feed-back, and K9 loses all control of his memory and programming. He becomes a danger to everyone and starts his self-destruct programme.

A vigilante group of former police officers discover that the Department are upgrading the CCPC’s with Alien tech, and make a stand by holding Gryffen hostage. K9 and Starkey battle the intruders whilst Darius faces up to his past.

Thorne entices K9 to hand over his regeneration disc in exchange for his missing memory chip. As a double cross, the fake chip contains a sequence turning K9 into a bomb. Starkey is taken by a Jixen who has a few surprises for K9 and friends too.

A strange phenomenon occurs in the STM that heralds the imminent arrival of a Korven invasion. Thorne is plotting to help them and has as his back-up a sinister giant creature that has K9’s regeneration disc implanted making it an indestructible weapon. K9 faces his biggest threat ever.