One of the crew of the Space Shuttle that was sent to the Moon to investigate the Sorson base constructed there. He was rescued by the Tomorrow People when the shuttle was caught in the middle of a battle between the Sorsons and the Thargons. 

The other crew member was Morgan Evans.

A race of aliens that can travel through space unaided. When they reproduce they leave 'eggs' on a planet. The eggs take the form of the dominant life form on the planet. When the eggs hatch they need a large amount of violent energy to allow them to transform into their adult form. The adult form is a glowing sphere, in this form they leave the planet. On Earth the Denagelee take human form. 

A Denagelee hatched at the end of the Roman Empire. The violence she required caused the destruction of the Roman Empire and could have caused the Dark Ages. The Denagelee returned to Earth and left several thousand eggs. One of the eggs was Robert, a pupil in Stephen and Elizabeth's class. 

One method that the Denegelee use to create violence is to split people into factions following the colours blue and green. People then develop an irrational and violent hatred of people that follow the other colour.

The grandson of Lieutenant General McLelland. He was a student at Glen College, and was in charge of the dormitory where Stephen was placed when he went undercover. 

He was also in-charge of the new members of the Doomsday Men, and often selected boys from the school to join them. 

After he was re-educated he helped the Tomorrow People defeat General McLelland.

She is an American university researcher currently investigating the reports of the Loch Ness Monster. She and her team of researchers are based in a hut on the shores of Loch Ness, but stay in Bruce Forbes' hotel. 

After the Loch Ness Monster hoax she loses her grant, but manages to get a new grant to investigate the ghosts at the hotel.

The headmaster of Glen College. He is also a member of the Doomsday Men

See Lord Dunning.