SciFi

Donna heads back to the city to find the Doctor, whilst the Doctor heads for the TARDIS.

Donna was starting to feel ill, the sickness was sudden and left her disorientated.
The city was in view but kept going in and out of focus and she was beginning to feel panic.
She soldiered on until she could make out a shape of someone coming towards her then collapsed in a heap.

"Help me get her to her feet", implored the Doctor.But Aattah and his armed guard kept their distance. "We have seen this before Doctor", Aattah said, "She has the sickness, she will die within the day".

"Not if I can help it". replied the Doctor,lifting her limp body over his shoulder.
"We have to make it to the TARDIS, I can help her there, I am a Doctor don't you know".

Carrying Donna's dead-weight across the sandy surface was arduous, but the Doctor soon reached the TARDIS. Using his new trick he snapped his fingers and the door of the TARDIS opened.

Accompanied by Aattah the Doctor entered inside whilst the guard stood outside. Aattah was awe struck and the difference in size inside the TARDIS was to out, but aware of the Doctor's predicament he didn't ask.

The Doctor carried Donna to an anti room where a variety of emergency equipment was stored and laid her on a bed. He then beavered himself around her linking her to a variety of test equipment.

After a while he spoke to Aattah. "From these readings there is not much wrong with Donna apart from her body is beginning to granulate. From the inside out her organs are turning to sand, it is a very slow process, but it is already affecting her breathing and blood flow".

Aattah spoke. "We found this with or own, but the process was faster, maybe our metabolism makes the difference", he reflected. "In fact once bodily functions ceased the conversion to sand also stopped and the bodies just started to decay naturally. We didn't touch them as it proved to be contagious".

The Doctor looked up thoughtfully, "It is not a disease as such, but the actual atoms of the body are breaking down and losing cohesion, as if the electrons of the cells have slowed so much they are no longer bonded together."

The Doctor hit his forehead with the palm of his hand, "I'm an idiot why didn't I see this before. Yes, now I understand it all" Rushing off the Doctor soon returned with an apparatus that looked like a mosquito net made of fine wire mesh and covered Donna from head to toe. Plugging it in the Doctor said. "And now we wait".