This story was sparked off by a discussion on the Tracy Island Writers Forum about writing the Ultimate Missing Tracy Twin Sister story. However, when my muse got to work on it she decided to take a poke at a few other tropes as well, until we had canons exploding all over the place.

I acknowledge ITV as the current copyright holders of the series. My thanks to Tiylaya for her proofreading and the Gerry Anderson and his team for giving us a show that has lasted fifty years.

I shall now go and find a large rock to hide behind.

oooOOOooo

"Hi John. Good flight?"

John stood up from his seat on the couch that had just emerged through the floor of the lounge and turned towards his older. "Yes, thanks, Scott. What's all this about?" He nodded his head towards the other blond figure who had been occupying the seat beside him. "Alan doesn't seem to know."

Scott shook his head "I'm none the wiser. Father just said he wanted all of us together for a conference. He said to give you half an hour to settle in then we'd convene." He paused, "and he wants us all to be in uniform."

"But ..."

Yes, I know." Scott mimed quote marks with his fingers. "'Uniforms are only to be worn on official IR business'. But that's what he told me." He shrugged. "No doubt we'll find out at the meeting."

Alan had been looking around the room. "Where's Tin Tin?"

"Brains has sent her over to Mateo. She must be going to collect something big as he told her to use Tracy Three."

His brothers nodded in understanding; the twelve-seater executive jet was normally only used when their father wanted to entertain corporate clients or the family were bulk shopping on the mainland.

John stood and turned for the door. "Well, if I've only got half an hour, I want to have a decent shower and change into a fresh uniform."

Thirty minutes later, the boys returned to the lounge to find five chairs set in a row in front of their father's desk; clearly, this was going to be a formal meeting. Two additional chairs had been placed beside the desk, facing the row of five.

Jeff entered the room, followed by Kyrano and Brains. He looked at the assembled group. "Good, you're all here." He took his customary seat behind his desk and gestured for them to sit down, then, with a sideways glance at Kyrano and Brains in the chairs beside him, began to speak.

"Boys, I'm sure you are all wondering why I've called this meeting. International Rescue has been running for three years now, and I think we can all be proud of what we have achieved." His eye moved along the line of young men in front of him. "Now it's time to take the operation to the next stage, but before I do there are some things I need to explain. Much of what I am going to tell you will come as something of a shock, as a lot of things that you think you know are, in fact, untrue."

The Tracy boys exchanged puzzled glances; what was going on?

Jeff continued. "My story starts about twelve years ago when I had what I suppose could be described as a mid-life crisis. This was triggered off by the sudden death of my father in a car accident. As such events can, this made me think about my own mortality, and what I had achieved with my life. To an outsider it might seem that my life had been a success; I had walked on the Moon, then left the Space Agency to start my own business and was well on the way to becoming a billionaire by the time I was fifty. But in order to do all this I had sacrificed any notion of a personal life; I had no wife, no children to inherit what I had worked so hard to achieve."

There was a stirring in the row in front of him, but Jeff held up a hand to forestall any comments. "Yes, I know I said twelve years and I'm aware you can all do basic arithmetic; but hold on - things will become clear in a minute."

The boys exchanged glances but kept silent as their father resumed. "Not long after that, there was a mine disaster in Germany where scores of workers were trapped underground but the only equipment capable of rescuing them was a long way away and had to be transported to the site; many of the miners died before they could be freed. This gave me the idea of what I would like to do as my legacy; form a rescue service capable of transporting men and machines anywhere in the world, whenever they were needed. I spent some time working out what I would need - a base of operations, the machines capable of doing the work and a crew to operate them.

The base was the first thing I found; using my government contacts I found an old decommissioned SAC base which already had underground hangars and missile silos I could use for storing the craft I had envisaged."

The boys nodded; this part of the story was familiar to them.

"However, the solution to the problems of crew and equipment came when I encountered two men who had both done ground-breaking work in their own fields. I'll let them tell you the details."

Kyrano rose from his chair next to Jeff's desk. In contrast to his customary slightly stooped posture and self-effacing manner, he stood with his head high, his shoulders back and looking directly at the young men sat in front of him. "You call me Kyrano, and think you know something of my background. I have told you that before I came to work for Jeff Tracy I worked at Kew Gardens in England, and later as a chef in Paris. Those statements were not entirely true. My full name is Kyra No Littan, and I am one of the world's leading experts in genetic engineering. At Kew I was engaged in mastering the techniques of gene splicing and an accelerated ageing process that would make a plant produce ten years growth in six months.

From Kew I moved to Paris where I created not meals, but human beings; what the popular press call 'designer babies', perfecting the technique of taking basic genetic material and enhancing it to fit the requirements of my customers. As a sideline, I had been doing some work on cloning, but the law at present does not allow this work to be done on humans so when Jeff Tracy approached me and explained his ideas, I saw an opportunity to further my research in secret."

Jeff leaned forward to the row of young men. "So that's the truth of it, boys. You are all clones. This is why there are no photographs of your mother around the house, and why I never speak of her. She never existed."

This statement caused an uproar.

"You told me she died in a car crash!"

"No, a plane crash."

"I thought it was a ski-ing accident!"

"You said she died when Alan was born."

"He said WHAT?" Alan was on his feet, red-faced with anger, his fists clenched.

Jeff sat back, shaking his head. "I never was any good at keeping the story straight, was I? Sit down, boys, we haven't finished yet. Kyra No, please continue."

The youngest Tracy resumed his seat and Gordon put a comforting hand on his shoulder. All the brothers looked visibly shaken, unsure of what was to come next.

Kyrano looked at Scott. "You were my first clone, a straightforward copy of Jeff Tracy's genetic blueprint. You have often remarked just how much you resemble photographs of your father at the same age; now the reason should be obvious."

He paused for a second, glancing along the row of faces. "But we didn't want to make you all look alike, that would have caused comment, not to mention confusion! So I started experimenting. I had already found in previous trials on plants and animals that altering one part of the genetic code to enhance certain attributes would also alter the subject's physical appearance. So I made the second clone more creative and with the third I increased the intellect, which had the side effect of changing the hair colour to blond."

"Hold on," cut in John, "I'm the second eldest, not Virgil!"

Kyrano nodded. "This is true. My first attempt at Subject Yellow - I always colour code my cases for identification purposes - resulted in an unstable embryo. Fortunately I always store the original zygote so I knew it would be a simple matter to replicate it, but by this time I already had Subject Purple ready for the incubator, so that one was produced first before I returned to Yellow." He looked at the two young men with a quizzical smile. "You've never wondered why your birthdays were so close together?"

His eye raked along the row again. "When it came to Subject Orange I wanted to enhance motor skills, and for Subject White I increased the competitive drive. Looking at you all now, I feel proud of what I managed to achieve."

The Tracy boys exchanged looks of horror, white-faced at the knowledge that everything they believed about themselves was turning out to be untrue.

"Hang on," said Scott. "When did all this take place?"

"About five years before International Rescue started. When I bought the island, Kyra No moved in and set up his laboratory in some caverns that were part of the old SAC base. It's a part of the island you have never seen, totally isolated from the rest of the complex."

"But... but I'm nearly thirty! What about our memories? Our childhood in Kansas?"

Jeff nodded. "That's where our second expert comes in." He looked at the young man sitting next to him. "Professor? Would you care to continue?"

The boys watched as Brains rose to his feet, removing his glasses as he did so. He seemed more relaxed than usual when addressing a group of people and, as he began to speak, his stutter was noticeably absent.

"My story begins nearly sixty years ago when an English scientist named Ian McClaine perfected a technique of recording brain-wave patterns onto tape and transferring them into the mind of another person. The professor used his young son Joe for these experiments, as he felt a young mind would be more adaptable to new thought patterns. The World Intelligence Network heard of his work, and for a time Joe enjoyed a career as a secret agent - for who would expect a nine-year-old boy of being a spy?

Joe's career did not last as he grew older; a teenage boy is more likely to arouse rather than allay suspicion. But because W.I.N. had been involved the project never became public knowledge, and the professor, with Joe's help, carried on with the work. They were able to miniaturise the equipment needed for recording brain patterns from something that took up an entire room to a device that would fit inside a briefcase.

I first met the professor when I was a young man, studying at Cambridge University. It wasn't actually Ian McClaine who I met, he had died several years earlier; but Joe had taken to using his father's brain patterns almost continuously. Joe was interested to see if a person of my intellectual capabilities would be able to carry more than one brain pattern simultaneously, and this proved to be correct." He paused, smiling,. "You've never wondered how one person, however intelligent, could be an expert in so many fields - aerospace design, electronics, communications, robotics and medicine? I'd have to be at least ten years older to have had to time to master all of those disciplines!

That's why I gave myself the nickname 'Brains' as I was often more than one person; it also accounts for the slight speech impediment as sometimes if I'm asked a question I have several different personalities all trying to answer at once."

He looked down at his thick, blue-rimmed spectacles, turning them over in his hand. "I use these when I want to adopt extra personalities, but Joe gave me his father's brain pattern when he retired from the work, and I access that via a subcutaneous implant." He touched a spot behind his ear. "I used the same method to implant memories that I fabricated for all of you. Joe and I had discovered quite early on in our research that it was possible for memories to be created and imprinted on a permanent basis, though we found that this would only work on a young mind with no conflicting memories of its own."

Jeff took up the story. "Once you had been grown to the right age and given your childhood memories we started training you for International Rescue. There were a few mishaps along the way - Gordon's hydrofoil accident set us back a whole year, but being able to create a backup..."

"A what?" Gordon's voice shook.

Kyra No looked at him. "Do you really think you had survived a 400-mile impact without permanent damage? We had to start all over again."

"But, but... I remember going through all the rehab!"

Brains spoke this time. "Of course you do. That was your old mind struggling to teach your new body to do the things it already knew how to do. Luckily, I had seen the possibility of damage and always recorded a brain pattern from each of you when you had your monthly medical. Any gaps in memory could be blamed on trauma from the accident."

"So how come I still get back-ache?"

Brains gave a knowing smile. "Purely psychosomatic; the psychiatrist whose brain pattern I use has been quite intrigued. His theory is that your brain expects to have some lasting pain so your body provides it. Of course, we would never let you carry on as a member of IR if you did have any permanent damage, any more than we would let any of you operate equipment that had a known fault."

Just then the radio behind Jeff's desk crackled into life with Tin Tin's lilting voice. "Tracy Three to Tracy Island. Requesting permission to land."

Jeff thumbed the button. "Tracy Three from Tracy Island; permission granted. We're nearly ready for you. Wait downstairs and come up when you get my signal."

"Very well, Mr Tracy. Tracy Three out."

Jeff looked up from his desk. "Where were we? Oh yes. We began operating International Rescue and I was very pleased with the results, especially the way you had all bonded together to work as a team. However, it quickly became apparent that I had underestimated the number of personnel needed to carry out rescues and maintain the machines, especially when I could see you all needed some down time as well.

I discussed our options with Kyra No and Brains. I was against bringing outsiders in on the project; apart from security considerations, it was already clear that you each identified so strongly with your designated craft that you would not take kindly to sharing it with outsiders. Kyra No was willing to make a second batch of clones from the original zygotes, but Brains advised against this - you were all far too much alpha males to want to share, even with another copy of yourself."

"Thank Pete for that," muttered Alan to Gordon. "Can you imagine having two Scotts bossing us around?"

Jeff continued, "Then I remembered the old adage that men compete, women co-operate." He gestured to the Asian man beside him, then lifted his watch. "Tin Tin, you can come in now."

"It is a relatively simple procedure to remove the Y chromosome and replace it with a duplicate of the X". As Kyra No spoke, the stairs leading up to the balcony rang with the tread of many feet.

Tin Tin entered the room at the front of a line of young women. The boys watched in horrified fascination as she led ten blue clad figures to stand in front of Jeff's desk. They could see that there were two sets of five, with a pair of girls each wearing a sash identical to their own. The only difference was that one group had red collars to their uniforms and red boots, while the others were green.

The girl at the left end of the line stepped forward. "Red team reporting for duty. FAB!"

Her movement was copied by the girl at the opposite end. "Green team reporting for duty. FAB!"

Jeff nodded. "Thank you Scarlet, Sage. Girls, please turn round and meet your brothers." He got up from his desk and walked around so he could see both groups. "Boys, these are your twin sisters. They are the same age as you biologically, they have your genetic pattern and have been given your memories up to the time of your most recent scans. Both teams have spent the last six months training in rescue situations and more recently acquainting themselves with the IR equipment in simulators on Mateo Island. Once they have had chance to familiarise themselves with the real craft they will be fully operational.

Boys, you are now the Blue team and will live in the Tracy villa while the Red and Green teams will be quartered in the Round House and Cliff House. I will work out a schedule later on, but my plan is that each team from now on will have one month on operational duty, one month on maintenance and one off-duty." He smiled. "We will leave you for a while to get acquainted, but I am delighted to say that Phase Two of Thunderbirds is now Go!"

As soon as the older men had left, Scott approached the two slim figures wearing blue sashes. "If you think I'm letting you fly Thunderbird One," he hissed through gritted teeth, "you can think again!"

"Are you so sure about that, Scott? We know you can be determined, but that means we can too!" replied Scarlet with a dangerous smile.

"Yes," responded Sage, her expression echoing her sister's. "Just imagine what Father would say if he knew what really happened that night in Paris when you and Virgil went to the Folies Bergere."

Scott paled. "You wouldn't!"

Scarlet's smile widened. "Wouldn't we? The question to ask yourself is what would you do to get your hands on Thunderbird One?"

oooOOOooo

Half an hour later, when Jeff returned to the lounge, everything seemed peaceful. Scott and his sisters had disappeared, though the half-open panel to Thunderbird One's hangar seemed to indicate where they had gone. Virgil was at the piano, playing a complicated duet with one sister - was that Violet or Victoria? - while the other leaned against the instrument, turning the pages of the sheet music at the appropriate moment. John and his opposite numbers had their heads together over some diagrams spread over the coffee table, and he could see a glimpse of three more blond heads on the balcony.

Then he caught sight of the three redheads huddled together in one corner, whispering. As he watched, one turned to scan the room then back to her siblings, wearing a smile that sent a chill through Jeff's heart. For the first time he began to wonder if this whole scheme might not be such a good idea after all.