The series follows a group of ten children in modern Britain, where an experiment at a Large Hadron Collider-like facility, the Sparticle Project, goes wrong, sending anybody aged 15 and over into a parallel dimension at exactly 11:11 am.

However, as the world's resources start to dwindle and daily survival gets harder, the youngsters resolve to bring the adults back by venturing to the top secret 'Sparticle Project'.

After discovering her Mum and older sister missing, a scientifically minded young girl called Kat takes charge of Liam, the small boy next door.

One of the tribe, a young girl called Reese, soon starts to experience strange events, which eventually turn out to be the manifestation of her own latent psychic powers.

The 'Sparticles' tribe then split in two: the 'Ranchers', Tia and Jeffrey (who has cerebral palsy), who stay at City Hotel with the two younger kids, Liam and Frankie, and the 'Questers', (Sadiq, Kat, Jordan, Ami, Holly and Reese), who go in search of the Sparticle Project.

One year later, the team continue to attempt to bring back the adults by locating the Quantum Nexus after it is discovered that the key unlocks a further clue leading to specific treasures that will guide the children there.

After following clues relating to the "Artos" tribe, the Sparticles are joined by Serena, who was secretly a double agent, in stopping Fizzy, Ernesto and Holly from destroying the Quantum Nexus with Reese, who switches sides after receiving a warning from Muna.

In the third season, the world is taken over by the newly arrived Queen Kylie, who locks up the remaining Sparticles (Sadiq, Reese, Serena, Holly and Frankie).

While travelling around the country in one of Queen Kylie's stolen tracker vans, Reese discovers "The Circle of Perpetual Time" which, when 7 sensitives are linked up with it, will be able to send the parents home using the power of an energy-boosting Comet.

Included in the main cast were: 16-year-old Megan Jones as Tia; 8-year-old Oliver Bell as Liam; Wesley Nelson (who has cerebral palsy) as Jeffrey; Karim Zeroual as Sadiq.

The children decide to choose who goes on the road to the Sparticle Project and who stays behind to look after Liam and Frankie by an 'Apprentice'-style challenge to source power for the City Hotel.

The Questers discover a fairground, where Jordan, Holly and Ami take being kids way too far, and nearly kill themselves on a runaway waltzer, until Muna (a child caught between the parallel worlds) comes to the rescue.

Note: Guest Appearance of Muna and Doomsday Dora A postcode given to Reese via Psychic Sarah at the fairground leads the Questers to a simulator where scientists were trained how to run the Sparticle Project.

While the team are on their way to the Sparticle Project, Ami is captured in the woods by the Water Rats – a group who love life messing around on the river.

Reese 'sees' Muna again and with the help of Tamsin, one of the village kids, Kat figures out that the wormhole events are occurring at points where laylines intersect.

Jordan and Ami have gone to France, Kat is sorting out the nuclear power plants but everyone else reunites when they realize the key from Doomsday Dora fits into a stone head.

Holly and Serena break into the museum and use an ogham has decoder to translate the message on the Stone Head, which was written on a piece of paper that they stole from Reese.

The Treasure Hunt is coming together with the discovery of another vital clue in the race to the Quantum Nexus, but the return of Ernesto leads to questions – exactly whose side is the Rebel on?

Sadiq, Holly, Frankie and Kim are locked up while looking for the boy, Orion, but are soon rescued by Reese and Aris before the Bounty Hunters find them.

Note: Fizzy, Bryan and HoloDora are absent in this episode The Sparticles head to a 'Quantum Anomaly' known as 'The Zone' to visit a sensitive with healing powers so he can make Holly recover from a mysterious illness.

Meanwhile the bounty hunters chase Reese and Aris into a Quantum Fracture where the two find themselves in the adult dimension, and manage to download HoloDora onto a tablet and return home to continue on with the mission.

Serena and Ernesto take Fizzy and Bryan's jeep (which the Fisher tribe stole the keys for) and part ways which they go to the citadel to rescue Orion, while Sadiq and the others search for the sixth sensitive.

Kylie uses this information and takes matters into her own hands by heading to the Circle of Perpetual Time with the after overhearing Dora and Erimon plotting against her.

The Sparticles leave the mansion with confirmation that Orion has been broken out of the citadel and that Kylie is planning to block the Sensonet at the Circle of Perpetual Time.

Dora and Erimon arrive with the transmitter, and Aris discovers Kylie has been lying to him and rejoins the Sparticles who believe The Keeper is the final sensitive.

The Neuroscrambler breaks down, due to HoloDora's interference, Kylie orders Dora to repair it, and threatens to push Erimon off the cliff if she doesn't.

Dora attempts to fix it but HoloDora messes with the Neuroscrambler's coding, leaving it stuck on mind-wipe mode, meaning the only way to save the sensitives is to turn it off.

HoloDora shows Kylie, Erimon and Dora and image of Holly and Ernesto's daughter, and explain that if she goes ahead with her plan, she will fry her mind.

She releases the energy into a portal, which sends, Kylie, Erimon, Dora, Bryan, Kim, Orion and all the other teen parents back to their times.

Note: Final appearance of Sadiq, Reese, Aris, Frankie, Holly, Ernesto, Serena, Kim, Kylie, Dora, Erimon, Fizzy, Bryan and HoloDora.