The thing in the box was about the size of a small play football, and multi-faceted like a ball is, but made of many more sides. As her head reeled she tried to work out if there was a name for a solid shape like this. The largest she knew was icosahedron with 20 faces. But this was more. It was like a huge diamond. Bigger than the biggest diamond in the world.

It COULDN’T be a diamond, could it? She lifted it in her hands and it had the feel and weight of something that SHOULD be a diamond. She owned three real diamonds in a necklace and earring set she inherited from her Aunt Lavinia. The biggest one in the necklace was about an inch across and felt heavy the way this much larger one felt heavy.

So The Doctor needed her to look after what must be the biggest and most expensive diamond in the world… in the universe. Why? Had he stolen it? She dismissed the possibility at once. The Doctor had a cavalier attitude to laws and rules – and other people’s hearts – but he wasn’t a thief. If he had to ask her to take care of it there must be a good reason. Somebody else wanted to steal it, for example. Perhaps it was the crown jewels of some world where revolution was imminent and it had to be hidden until the true king could claim it.

She laughed at herself, making up fairy stories about it. Then her thoughts wandered to how much a diamond that size could be worth. The biggest diamond in the world was the Koh-i-Noor, wasn’t it, or was it the Cullinan diamond? Either way nobody dared put a price on THEM. And this was WAY bigger than the two put together..

It was worth more than everything she owned. Her house, her car, every stick of furniture. Worth all the houses and cars in the street, and THEN some. It was truly priceless.

And she was holding it in her hands, sitting at the kitchen table.

There was a knock at the window. She nearly jumped out of her skin. She dropped the diamond back into its box and hastily covered the lid. She looked around at the grinning face of the milkman. Of course, it was Friday afternoon. He wanted paying. She grabbed her handbag and hurried to the back door.

“Afternoon, Mrs Smith,” he said. The milkman always called her MRS Smith. He was in his mid-50s and a bit old-fashioned and couldn’t contemplate a woman of her age who hadn’t been married at some time in her life.

“Good afternoon,” she replied as she fumbled in her purse for change. She was flustered and dropped the coins. She bent to pick them up and dropped her handbag, spilling everything else. She grabbed for her lipstick applicator as it rolled away. She couldn’t lose THAT.

She stuffed everything back in her bag then stood up with a handful of change and counted out what she owed the milkman for the two pints a day that she used. One pint a day it was at the moment, because Luke was away and Maria and Clyde as well, and she was only making tea and coffee for herself. She replied to his small talk about the weather and waited as he wrote the payment in his little book.

At last he turned and walked away. She tried not to slam the door shut before he was out of earshot. She locked it and pulled down the blinds on the window and turned and looked at the fantastically valuable thing sitting on her kitchen table and had a moment of panic. She half expected a horde of Yeoman of the Guard from The Tower of London to descend on her house and claim it as part of the Crown Jewels of England or…

No, she told herself. Thieves wouldn’t be breaking in to her house to steal it, because thieves wouldn’t know it was there. The Doctor and his friend who gave her the parcel were the only other people who knew she had it.

And the milkman?

No. He wouldn’t have seen it from the window. No. the angle was wrong. She would have covered it with her body as she sat at the table.

No, he couldn’t have seen it?

Could he?

Even if he had, he wouldn’t do anything. He was the milkman. Dessie, his name was. Like Des O’Connor, he said to anyone new on his round. He always whistled a daft tune called Dick-A-Dum-Dum that Des O’Connor was famous for so far back that Sarah Jane didn’t want to admit to remembering. Maria once asked ‘Whose Des O’Connor’ and REALLY made her feel old!

She stopped herself in mid-thought. She was totally rambling. But the POINT WAS, Dessie, the Milkman, was harmless. Even if he HAD seen her holding the diamond he would have thought it was a nice bit of Waterford Crystal that she was polishing.

And besides, there was something in this house that WAS worth more than a diamond, no matter how big. She grabbed the box and went upstairs, and through the door and upstairs again to the top floor of the house where few people ever went except her. The place where everything of special value and significance to her was.

“Mistress!” said a voice with a strange, inorganic cadence because it CAME from an inorganic voice box that called to her as she came up the stairs.

“You shouldn’t call out like that,” she told the robot dog called K9 as he approached her, his metal tail and ears wagging joyfully. “What if it wasn’t me?”

“I detected the rhythm of your footsteps and your pheromone pattern. Mistress, Mr Smith has detected an unusual power source in the house.”

“Correction,” said the voice of Mr Smith, the huge computer console that covered one wall of the attic room. Unlike K9, the computer had a soft masculine voice that sounded completely Human and real. Should a psychologist ever see inside this room and hear Mr Smith they would no doubt draw all kinds of conclusions about her need for a computerised ‘husband’ and if they found out that Mr Smith was the occasional pseudonym of her ‘unrequited love’ that would probably fill another page of the dossier.

Nuts to psychology, Sarah Jane thought.

“What was that, Mr Smith?”

“The power source is now within this room.”

“What?” Sarah looked around nervously. K9 and Mr Smith were themselves unusual power sources. K9’s internal battery was, according to him, harnessed dark matter. She knew if she asked him what that was she would feel her eyes glazing over in about two minutes and her brain shut down in defence three minutes after that.

As for Mr Smith, he came to her from some old friends at U.N.I.T. They had built him from a section of the old TARDIS console that The Doctor had taken out to work on in his laboratory at U.N.I.T HQ. The old, Doctor, the old, old Doctor, as she thought of him. Her FIRST Doctor.

U.N.I.T’s best scientists had created a computer that used that technology but they couldn’t make it work. Only someone who had travelled with The Doctor and had the imprint of the TARDIS on them could operate it, So they reminded her that she HAD signed the Official Secrets Act in 1973 and let her take it home with her.

Rambling again, she reminded herself. But the point was, if Mr Smith and K9 both said there was an unusual power source in the room, not only was she ready to believe them, but she knew it would be a VERY unusual power source indeed.

“What is it? Where is it?”

“It is in your hands, Mistress,” said K9.

“The diamond?” She stared at it. She realised it had a luminosity of its own. It didn’t just reflect light like a diamond’s facets. It was a SOURCE of light.

“Bring it here,” Mr Smith said. “I will analyse it.”

“I do not believe it is harmful, mistress,” K9 added.

“I’ll be the judge of that,” Mr Smith responded.

“No squabbling, you two,” Sarah Jane said to them. “Anyway, I’m sure it isn’t harmless. The Doctor sent it. He wouldn’t send me something dangerous.”

K9 wiggled his ears and made a noise that sounded like a cough.

“All right, he wouldn’t DELIBERATELY send me anything dangerous,” She amended. She put the diamond into Mr Smiths analysing receptacle and he hummed as he analysed. Not as a computer hums, but actually humming a TUNE.

“I’ll Get By With A Little Help From My Friends.”

Both the friends she was getting by with had computerised brains. Sarah Jane wondered momentarily what that same psychologist would make of that.

Nuts to psychology.

“Yes,” Mr Smith said at last. “The diamond IS the power source.”

“It really is a diamond?”

“Correct. The outer substance is 100% pure compressed carbon, commonly known as diamond.”

“OUTER substance?” Sarah Jane looked suspiciously at the diamond that glowed from within. “What about the inner?”

“The inner part consists of….”

Mr Smith’s voice speeded up as he reeled off what sounded like the whole periodic table and some elements that weren’t yet IN the periodic table as Earth science stood in the year 2008.

“You mean the inside of the diamond is made up of every element in the universe?” she said at last when he stopped.

“Yes.”

“My goodness.”

“The inside of the diamond contains a galaxy,” Mr Smith continued. “Observe, Sarah Jane.”

Mr Smith’s viewscreen shimmered and she watched a beautiful view of a galaxy of stars, billions of them against the blackness of infinity. No, not blackness of course. The black was also purple, red, yellowy bits. It was never just a blanket of uniform black. There was too much happening in the universe. There were dust clouds and supernovas and black holes and energy fields, Helixes. The universe was a busy, fascinating place.

And a piece of that universe was inside the diamond. Mr Smith was showing her a galaxy contained inside something the size of a small football. She reached and lifted it up and looked close.

She gasped.

It was TRUE. She looked close at a facet and inside she saw the swirling mass of stars. It was even better than looking at it on Mr Smith’s viewscreen. Because it was real - it was three dimensional. It was RELATIVELY dimensional, too. She looked at what should be only a few inches across and she knew she was looking at a billion miles. It wasn’t a miniature galaxy. It was a full size galaxy inside something a few inches across.

To anyone else that would have been mind-boggling. But she was Sarah Jane Smith and nothing boggled her mind any more. Especially anything that came from The Doctor.

Well, maybe one thing boggled her.

“Doctor, you sent me a GALAXY to look after!” she whispered aloud.

He said he trusted her.

He not only trusted her to look after the biggest diamond in the universe, but he trusted her to look after a chunk of the universe itself.

That amount of trust was mind-boggling.

There was a sofa among the various bits of furniture in the attic room. She dragged it until it was in front of Mr Smith and sat down on it. She held the diamond and looked into it again and found she could focus on a star, any star, in the whole mass of them, and it would appear closer and bigger, like looking through a really fantastic telescope. Mr Smith’s screen displayed two dimensional pictures and schematics with dimensions and other data, but the view in the diamond was better.

She was looking at a star with two planets. One was small and hot, a desert planet with no water. The other was large and frozen. Its atmosphere, Mr Smith told her, was frozen methane. A very hostile environment.

“Well,” she said. “I know there are LOADS of planets that do support life. This galaxy must have some. I can look, can’t I?”

“Observation of the galaxy will not harm it,” Mr Smith answered. “Nor will you be harmed by the observing.”

“All right, then,” she said and she made herself comfy on the sofa, snuggled in the cushions. She focussed on another star and it came into close focus. This one had four planets, again the closest to the star was hot desert, and the one furthest away was frozen. But the two in the middle were a lot like Earth. They had frozen poles and oceans and continents. She focussed on the inner one first. It had one huge continent. Mr Smith said it would probably split up in time into smaller ones. There were tectonic instabilities that made continental drift inevitable. But for now there was one continent. A desert in the middle, and green and watered around the edges.

It had people. She thrilled as her eye was able to focus in on a settlement near the edge of the continent. A primitive one. The people looked like the Neanderthals of prehistoric Earth and their dwellings were just mud and straw. But they were people.

The other planet was different. It was advanced. More advanced than Earth was now. It had flying cars and huge cities of great shining towers. It had bridges that spanned whole seas. It had billions of people.

Sarah Jane watched, fascinated, and more satisfied than she had been for so very long. This was almost as good as travelling with The Doctor. She could see these wonderful places, these fantastic people on distant planets. All the things she missed since he left her back on Earth.

The afternoon passed by as she watched the planets of her own galaxy. She felt like a god looking down on the people, the creatures, the myriad life that she observed. It was K9 who reminded her to go and get some food for herself. It was too late for tea so she made supper instead and ate it in the room, watching Mr Smith’s screen until she had finished eating and could hold the diamond again. When it was bedtime, she locked up the house and brought a duvet and pillows and settled down on the sofa, still holding the diamond, and watching the views of the galaxy inside it that Mr Smith displayed on his screen. K9 sat beside the sofa, a good dog on guard duty, guarding his mistress as she guarded the galaxy.

Below in Bannerman road, in the shadows, something watched the house and bided its time. When its scans showed that the only organic occupant was asleep, it moved towards the house, looking for a weak place where it could get in. All dwellings had weak places. And it knew where to find them.

To Be Continued....