Ben discovers that there is a portal to a parallel universe, he has a sister, his mother is a Guardian of the Parallax, his best friend has a sneak thief double from another world and large flying purple insect things want to bite him.
Ben follows Francis Zapmeister into the third parallel universe, where hippies are all the rage. There, they work out an arrangement, and returning to Ben World, he and two Francises work out a scam to pay back Ben's Martin.
Katherine's Melinda goes exploring in Ben's World. Melinda and Florence the Chicken find a new portal that leads to a hi-tech rubbish tip. The kids arrive to rescue her and are attacked by Welkin, and Ben is bitten.
Katherine and Ben play pass the parcel as they each try to offload Francis Zapmeister's loot from the trip. They're almost caught and their inter-Parallax travels exposed, but Veronica saves the day.
Ben discovers that by pressing the portal sign he can travel to a new world. He meets Mundi and is introduced to a town where people live on treetops. It's fun until he is scratched in a Krellick attack.
Ben is sick as a result of the Krellick scratch. His friends travel to Forest World to get the antidote but wind up in a huge battle against the Krellicks. They are losing when Veronica saves the day.
Ben visits Desert World and has to use his head after his rash actions land him in strife. Katherine is sent to Forest World, where a night of singing and dancing teaches her to open up to her emotions.
Tired of the Martins giving them a hard time, Ben and the gang get their revenge. They lure the Martins from each of their worlds to Forest World and the Martins are terrified when their "reflections" talk back.
In Techno World, Francis Zapmeister meets Betti, a mysterious woman who looks exactly like Veronica. She has plans to remove "aberrants" from the Parallax to make the worlds a better place.
Veronica reveals that Betti is her twin sister, and that the Welkin and Krellicks are part of Betti's army, sent to destroy the remaining Guardians to prevent them interfering with her plans to blandish the Parallax.
To distract Betti from her search for the newly-found Guardian, Veronica sets herself up as a decoy in Techno World. Ben and Katherine arrive in time to see Veronica disappear in front of Betti in a blinding purple flash.
Jeremy convinces Ben that Veronica must be still alive. Ben sets off Spy Boy but is lured into a trap. Katherine arrives just in time to rescue him. but has also accidentally led his local Tiffany to Forest World.
Betti disguises herself as Veronica and goes to Ben's world, determined to find the mystery male Guardian, but Jeremy, the kids and Mrs Dawes fool her.
Ben recruits Jeremy and Stefan to help fight Betti, but the two dads immediately lock horns the moment they meet each other. Ben discovers that the Staves can act as intercoms, and that Veronica is still alive.
Betti lures the gang to Techno World. The kids, assisted by Jeremy and Stefan, fight the Krellicks and win the battle. But Betti wins the war when she and Spy Boy blandish the world.
Ben and Katherine find Otto, the lost Guardian of Forest World. Otto reveals that Veronica's pots are a map to the Reading Room of the Parallax. Katherine reveals her existence to Betti.
Ben finds Otto in Techno World, but they are tracked by Spy Boy. Katherine speaks to Betti and tells Veronica, in code, that Ben is still alive. Otto tells Ben the purpose of the Reading Room.
The two Martins want to know everything about the Parallax. Betti buttonholes Katherine's Martin - the greediest - and, shows him the possibilities of a Parallax that includes Techno World in return for information about Katherine.
Betti finally gets her meeting with Katherine and proudly shows her intended 'partner' around "Garden World" as an example of how people live happily and prosper in a blandished world.
Betti is on Katherine's trail, and now she has lackeys. She has recruited the Martins from Ben's World, Katherine's World, Techno World and, most recently, Forest World to be her own personal pursuit team to find Katherine.
Ben and Katherine find another Orb in Ben's world, which transports them to the Reading Room. They view the different worlds and find Veronica imprisoned in Garden World. Francis Surfer volunteers to go and rescue her.
Betti sets a trap for Ben and Katherine at the Garden World portals. Francis Surfer finds Veronica, and helped by Spy Boy and Otto, the gang manages to get home safely. A furious Betti destroys Ben's home..
The unconscious Veronica is taken to the surf shed sanctuary to recover and Ben and Katherine head for the Reading Room intending to sort Betti out once and for all.
