DOCTOR WHO IN DETAIL

At the International Gallery in London security guards are on lookout, guarding the Cup of Athelstan. They are not monitoring the room as a woman dressed in black descends on a wire and lifts the cup, replacing it with a toy. When a security guard looks round and notices the cup he raises the alarm. The woman escapes in to London as the police arrive and arrest her accomplice. She jumps on to London bus. As she sits down, the Doctor sits down next her, offering her a piece of Easter egg.

Inspector McMillan notices the woman on the bus and sets off in pursuit. A device for detecting Rhondium particles starts beeping in the Doctors pocket as the bus heads for the Gladwell Park tunnel. Cameras in the tunnel monitor the bus's progress, and the police block the exit. Another woman on the bus, Carmen, is hearing voices. The Doctor tells everyone to hold on as the bus starts shaking violently. The bus never makes it out of the tunnel.

Instead it has been transported to an alien planet. The Doctor is the first to leave the bus on to the planet's surface. All that can be seen is desert, and Carmen is still hearing voices. Barclay, one of the passengers, noticed the Doctor had a device, and wants to know if the Doctor caused the transportation. The Doctor says he was using it to track a hole in the fabric of space. The hole got bigger and the bus went through. To demonstrate the Doctor throws sand to show the door. The driver tries to run through the hole, and only his skeleton returns to London. In London, when the skeleton arrives, the police Inspector realises they need help, and calls in UNIT.

The bus protected everyone on the way to the planet, so the only way back is to free the bus from the sand and drive it back through. Inside the bus the woman thief takes charge, introducing herself as Christina, and everyone introduces themselves. The Doctor says the trip was an accident, but Carmen, who has a low level psychic ability, says the doorway was made for a reason, and that something is coming.

In London UNIT arrive and set up a temporary base. Captain Magambo takes charge.

On the planet, Christina sets about organising the escape. She digs out a small shovel for Nathan to start digging out the bus. Angela tries to start the engine, but sand has clogged up the engine. Barlcay starts to clean up the air filter. The Doctor and Christina then set off to explore, unaware that there is an alien ship on the planet, and inside they are being watched.

As they are wandering across the sands they see an approaching storm and rush back to the bus. The Doctor grabs Barlcay's phone, upgrades it using the sonic screwdriver, and calls UNIT (after first calling for pizza by mistake). He gets transferred through to Magambo. The Doctor needs to analyse the wormhole, and Magambo puts the Doctor through to UNIT's scientific advisor, Dr. Malcolm Taylor. He is awestruck to be talking to The Doctor.

Malcolm has already started to analyse the wormhole. Taking the phone the Doctor takes a picture of the storm and sends it back to Malcolm. There is something shining in the storm. Christina hears a clicking noise, and sees a humanoid insect holding a gun. The insects forces the Doctor and Christina at gun point to is ship that has crashed on the planet and has broken in to two.

The ship is made from Photofine steel. Whilst it's hot on the planet, the inside of the ship is cold. There are more aliens inside. The aliens have a telepathic translator meaning they can understand the Doctor and Christina, though it only works one way. The Doctor is able to translate, and the aliens say the Doctor and Christina have committed a crime against the Tritovore race. The Tritovores accuse the Doctor of coming to the planet in the 200 (the number of the bus) to destroy them. The Doctor tells them they have made a mistake, and that they are here by accident as well.

Using the equipment inside the spaceship the Doctor learns they Tritovores came to San Helios, the planet they are on, to trade. Video of the planet show a green planet with a sprawling city. San Helios is now just a desert. The planet, and the population of the planet, have been turned to sand.

Malcolm calls the Doctor to tell him the wormhole is getting bigger and has expanded to four miles in diameter. Magambo has even cancelled flights over the wormhole. Nathan, on the bus, calls to tell the Doctor all the fuel on the bus has been used.

The Doctor had used the spaceship to launch a probe in to the sandstorm. The probe starts to send back pictures, and the storm is not a sandstorm, but a swarm of creatures. The creatures are on their to the wormhole, and are destined for Earth.

The Tritovores didn't crash due to the wormhole; ten miles up the engine stalled. At the bottom of the gravity well there is a crystal nucleus. The ship might be a write-off, but the crystal, if intact, could power the bus. The Doctor grabs some comms equipment, and leaves Christina at the top of the shaft as he tries to find a way down. Out of sight Christina sets up the equipment she used at the gallery, and jumps into the gravity well. The Doctor stops her just before a security grid. She operates a control to cancel the grid, and makes her way down to the bottom.

At the bottom Christina finds one of the creatures in the swarm. She manages to grab the crystal as the creature, which had flown in to the engine causing it to stall and crash, follows her. On the way back up she is able to reactivate the security shield, trapping it.

The Doctor says they should leave, but the Tritovores will not leave their ship. Both of the Tritovores are killed when the creature escapes in to the control room. The Doctor and Christina run back to the bus. It wasn't the crystal that was needed, but the clamps that held it in place. The Doctor attaches one clamp to each wheel. In order to get it to work the Doctor needs gold - the Cup of Athelstan. He hammers the cup to make connections, and the bus is able to levitate, and fly back through the wormhole.

Malcolm is able to close the wormhole, but only after a few of the creatures have made it through. The UNIT soldiers start firing at the creatures, and are able to kill them using heavy weapons.

When the bus is safely on the ground Christina is taken in to custody by the Inspector, but the Doctor frees her using his sonic screwdriver, and she escapes in the bus.

Everyone is cheering when the passengers are back and the creatures are stopped, until Carmen gives the Doctor a warning: His song is ending. It is returning through the dark, and he will knock four times.