DOCTOR WHO IN DETAIL

On Kastarion 3 two survivors of patrol are returning to base across a burning barren landscape. Caros is leading John Francis Vater, who has been blinded. They pause and John to take a call from his daughter, Splice. They have wandered into a fresh minefield, suggesting the mines have migrated, and there is heavy fog. As they make their way John tells Splice to go to bed, and brush her teeth, ending the call with "Kiss Kiss". Carson warns John about an ambulance ahead of them, worried it will detect John's injured eyes. Carson moves ahead and falls into a crater - and steps on a land mine. There is a brief explosion and John is left alone. The ambulance detects the explosion and finds John. After a scan the ambulance determines that John's blindness will take too long to recover from.

The TARDIS is already on Kastarion and the Doctor hears John's scream and rushes to investigate - but stops when he puts one foot on a landmine. Ruby follows more cautiously and hears the Doctor singing the Sky Boat Song. The Doctor tells Ruby he is getting his "zen" on as Ruby sees the landmine. Ruby describes the landmine to the Doctor. The landmine is a smart mine made by Villengard. It has a row of green lights that illuminate as it attempts to work out of there is a live target stood on it. If the Doctor shifts his weight too much it would explode.

The Doctor is more concerned with the scream he heard and tells Ruby to check that out first. Reluctantly Ruby goes to investigate, and the Doctor asks her to find something heavy, like a rock, to act as a counter-balance. Ruby finds an odd canister dedicated to John Francis Vater. The Doctor tells her that's it doesn't just contains the remains of a dead body, but is the remains of a dead body. But the canister is heavy enough for the Doctor to use as a counter-balance, and he is able to at least put down his other leg.

The Doctor thanks John and at the mention of his name a hologram appears. The hologram is an approximate AI incorporating some elements of his former personality, including the phrase "kiss kiss". When asked about his termination John explains the ambulance humanely terminated him as his recovery was beyond acceptable parameters for the conflict budget. Ruby is astonished John was killed by an ambulance, and the Doctor explains how patients are expensive to the Villengard algorithm which is tuned to keep the conflict going as long as possible so weapons continue to be purchased.

As the hologram disappears Splice appears after hearing her daddy's voice. When Splice tells the Doctor her full name the hologram activates. Ruby manages to hold on to Splice to stop her hitting the Doctor or any further landmines. As the Doctor tries to calm down after an adrenaline rush a light appears and Mundy arrives. With Mundy pointing a gun at him the Doctor asks about the war. Mundy says they are fighting the Kastarions, but admits they have never seen one. Mundy insists the Doctor lets go of John's remains. If he does it would trigger the landmine. Mundy explains the landmine has a fail-safe and it will explode after a certain amount of time.

Mundy fires pulses into the Doctor's arm, trying to get him to drop the canister, alerting an ambulance. The Doctor asks Mundy how the landmine works as it does not contain explosive. Mundy explains that a quantum-level chain reaction in the subject's DNA is the explosive, and the Doctor says as a Time Lord he is far more complex, and explosive, than humans. When Mundy scans the Doctor she realises if the Doctor explodes he would take half the planet with him.

When the ambulance appear after detecting combat Mundy tries to shoot it, but the algorithm will not let her. The ambulance fires two probes into the Doctor. It struggles with the Doctor's identity and vital signs. Ruby takes Mundy's gun and starts firing into the air. The ambulance disengages when it detects new combat. Mundy tells Ruby to shoot her arm so the ambulance detects an injury. At that moment Canto arrives and, seeing Ruby aiming at Mundy, fires at Ruby. She falls into the crater where the ambulance attends. The ambulance fires probes into Ruby. It identifies her with a calendar age of 3,082 years, but cannot find an next of kin. Snow starts to snow, giving the Doctor hope, but stops when Ruby's vital signs start to fail. As Ruby is unordained the ambulance withholds treatment.

The Doctor explains to Mundy that there is no-one else on the planet. There are no Kastarions, just the algorithm maintaining an acceptable casualty rate. The Doctor tells her the only way to end the war is to surrender. Mundy tells the Doctor only the Bishop could surrender - if there is proof there are no Kastarions. The Doctor calls up John's AI and tells it to download itself via the ambulance into the Villengard battle computer to find proof the planet is uninhabited.

With John's AI in the computer the algorithm starts to protect itself, and more ambulances approach the crater. The John AI is replaced with an ambulance AI warning of severe fines for interfering with the Villengard algorithm, and it says the Vater AI has been deleted. Moments later the Doctor's landmine glows red as the fail-safe countdown starts. As the countdown reaches the end ambulance says "kiss kiss". The ambulance then proceeds to revive Ruby, and the Doctor's landmine is de-activated.

Instead of just looking around the John AI must have been angry at what it saw and took over, calling a ceasefire to the war.