When intelligence agents around the world come under attack from alien forces, MI6 turns to the only person who can help- a certain Doctor and her companions. As they travel the globe in pursuit of answers, threats arrive from all sides, leaving Earth’s security resting on the team’s shoulders. But where will this planet-threatening conspiracy lead them?

Ko Sho Blo! Trigger-happy space police the Judoon are targeting 21st-century Gloucester. The Doctor, Yaz, Ryan and Graham race back to Earth in order to prevent them doing too much damage to the cathedral city. But who are they looking for, and what did they do to incur the wrath of the Judoon?

The mysterious “Praxeus” will cause the quartet to split up (never a good idea) to investigate mysteries all over Earth. And what they find will threaten all human life (again).