The 3rd and 8th Doctor are sent into the Citadel to investigate the Force-Field/Transduction Barrier Room. The 3rd Doctor chooses Jenny as his companion while the 8th Dr asks Chang and Grace to be his. They encounter members of the Outsiders. They discover someone's been tampering with the transduction barrier which protects all of Gallifrey from Invasion. An Old Friend is found.

Everyone is working hard to try to stop the coming Time War which is less then 2 hours away. The Tenth Doctor tries to get Romana to leave Gallifrey and hide. Tegan makes a startling discovery. When The Doctors discover that both their family and friends had been locked up, they demand answers and when they hear them, they are furious. Shashir springs his trap on the Doctors.

The 10th and 11th Dr are shocked to see Donna Noble on Gallifrey. The 2nd and 10th Doctors must travel to the Intergalactic High Council Space Station to retrieve the Sash of Rassilon. Jamie accidentally uses the same transporter pad which aged the 5th Doctor. The Doctors and their companions discover some other companions are trying to stop the murder of 5 delegates.

The First and Ninth Doctors arrive on planet Carina with Rose, Katarina and Lon seeking The Cornet. The leader Shemal is very eager to make friends with the Doctor and Gallifrey. But soon the Doctors strongly suspect there is evil afoot. Meanwhile Katarina stumbles across a barbaric practice. The Dr's and their companions must work to save a group of people from being executed.

Doctors 4 & 11 are trapped on planet Phaester Osiris, Homeworld of the evil Sutekh. Sutekh has been rescued from the temporal time-tunnel by the Black Guardian. Sutekh now desires revenge. Can the two Doctors find the ring and save Gallifrey? The Transport Pad is destroyed so the other Doctors must find another way to rescue them without giving themselves away.