Excelsor 3 is the codename for Theo and Otto's experimental Teleporter and Time Machine, which was the focal point of the TDRS movie, Event Horizon. It has a long and varied history, going through three phases of development before it was finally functional.


The "Excelsor" project was conceptualized in 1955 by Theo and Otto, during a motive power shortage on the Dark Railway. The twins began the project in order to assist Mr Dark with growing concerns that there was not enough motive power to keep the railway afloat as, at the time, the railway was borrowing locomotives from British Railways, and could be reallocated at any time.

At the time, there were only three locomotives owned by the railway company: Theo, Otto and Ryan, with two other engines on long term loan: 257 Squadron (who would later be purchased by Mr Dark) and James, a small Maunsell Mogul which was later destroyed in an accident. These engines were complimented by a cross section of other locomotives, but these would only operate services on the line for a few days before returning to their home sheds. The twins decided that something had to be done, as purchasing other locomotives at this time was difficult and costly.

Excelsor 1Edit

The first of the "Excelsor" projects was based on a theory regarding cloning locomotives in order to increase the amount of motive power on the railway, without having to physically borrow the engine from British Railways employ. A quote from Otto states the genesis of this idea: "Why can't we have one engine in two places at once?".

The basis for what would become "Excelsor 1" was an old shed located at the twins' "Lair", an abandoned quarry pit beyond the station at Soma, which was abandoned and cut off from the rest of the railway during the early 1900's. The twins, using their vast intellect, managed to develop a theory on cloning materials without having to physically build a new locomotive. In many respects, the idea worked in a similar way to how a modern day 3D Printer works, but in such a way that the original materials, elements and, essentially, the "soul", of the cloned locomotive were directly copied from the original, essentially sharing exactly the same "essence" of the original without having to manufacture and assemble everything again.

In their minds, it would be faster and cheaper to clone the engines that arrived on the railway, then keep them, sending the original back to British Railways. As mad as it sounded to everybody else (due to the fact that a new locomotive, at the time, could theoretically have been built and ordered from an outside builder), Theo and Otto, being mad scientists, were determined to make this theory work, and continued working on this project for two years before it was finally ready for a test run.

In order to test "Excelsor 1" (which, like the rest of the "Excelsor" experiments, resembled an old shed with a variety of random objects protruding from it), Theo made the bold move of allowing the machine to create an exact copy of himself. The machine was activated for it's initial test run late in 1957, around the time that James was destroyed in an accident.

The test run was, initially, considered a success, with an almost exact copy of Theo being created with the machine. Unfortunately, there was an unitended side effect of this experiment: during the cloning process, the machine had indeed duplicated Theo, but the clone had no "soul": Test conducted by the twins determined that the clone was "an empty shell, with nothing to indicate that it was alive at all. No reactions to tests, no speech, no thoughts. Nothing." 

The twins decided to see if the "clone" would actually "function" as a locomotive, which they thought might also jump start any "intellect" or "soul" possibly lying dormant inside the clone. Water was injected into the boiler, and the fire was lit inside the clone, but, somehow, the fire began to spread all over the cloned engine, causing it to erupt into a fireball, which ultimately destroyed it! 

Theo was deeply scarred by this experiment, later saying that "Our tests indicated that it wasn't alive as such, but I actually thought that, at one point, I could see out of it's eyes as it burnt up. I saw myself through those eyes. I felt the pain and the fear of it. Otto told me that it was nothing, just a hangover from the cloning process. But I beleive that part of my soul did end up inside that clone. I feel that a part of me died during the fire." He vowed never to experiment with cloning again after this experiment, which was deemed a complete failure. Otto secretly and discreetly disposed of the remains of the "clone" soon afterwards, hoping that his twin would recover from the trauma in time, which, with Ryan's help, he did.

Excelsor 2Edit

After the horrendous experiment with Excelsor 1, the twins began developing a new theory utilising the locomotives already present on the railway. By this point, 1957, James had been scrapped after his accident, and 257, suffering from the trauma of the accident, requested to leave the railway. This left just Theo, Otto and Ryan. This gave the twins an idea: what if they made themselves bigger, stronger and more powerful? Of course, after the disaster with Excelsor 1, the eventual test would have to be completed by using another, disposable test subject.

The twins began developing their theories, and, by the middle of 1958, were repurposing the original "Excelsor" with a new matrix, power supply and internal coding. Their theory suggested that they could potentially "deconstruct, then reconstruct" a locomotive with a different shape, size, density and design, on a molecular level. They took this further by actually designing a matrix that could change the atomic structure of an engine to, essentially, create an entirely new engine out of the original atoms of the subject.

Unfortunately for the twins, by the end of 1958, Mr Dark had managed to purchase two locomotives from British Railways, Dave and Brian , and was now borrowing another light pacific, Sir Eustace Missenden, thereby ending the apparent locomotive crisis. Never-the-less, the twins had come too far to abandon their project, and continued working on the project.

By December 1959, the machine was ready for a test, with the twins seemingly having optimized Excelsor 2 to function correctly. Before they used a "live" test subject, the twins managed to deconstruct a telegraph pole and reconfigure it into a pile of sleepers and rails successfully, and again with a pile of rubble, they created a rather grandeous table for Mr Dark's sitting room at Axley Manor. Feeling that their technology worked correctly, and could be optimized for other such reconstruction tasks, they began searching for a live test subject, which presented itself in January 1960 as a small diesel shunter which had been purchased by Mr Dark: Owen.

Owen, being young and impressionable, was brought to Theo and Otto's lair under the pretense of "participating in a grand tour of the railway", when really, he would become a "disposable" test subject. Owen was tricked into entering "Excelsor 2" and the machine was activated, with the twins reasoning that Owen, being such a small diesel, could essentially be reconfigured into a much larger, more powerful engine. 

Strangely, the machine did not function as originally intended, with Owen seemingly unaffected by the experiment. Owen was brought to Soma Quarry shortly after for further analysis, but suddenly, he grew to gigantic proportions, almost destroying the quarry! The twins, terrified and confused, worried what to do, when, just as suddenly, Owen shrank much smaller than he had originally been, before returning to his normal size! The twins theorised that his molecular structure were in a state of flux, changing his physical size, but not his density.

The twins deemed the experiment a "half success", and, growing fond of Owen, offered him his freedom. Owen, however, had learned about the overall goals of their project, and convinced them to continue with the project and volunteering to continue his role as test subject. Owen secretly wished that he was a bigger and more powerful engine, and the twins could potentially reconfigure him into something much more than he already was. Unconcerned, the twins modified Excelsor 2's matrix, and, several days later, the second test on Owen could begin.

Using plans stolen from Brush Traction, the twins successfully reconfigued Owen into something representing a Brush Type 2 diesel locomotive. Owen, feeling bigger and better than he had ever done, suddenly went rogue, feasting on the power that he now posessed, threatening Theo and Otto, and forcing them to send him back through Excelsor 2 to make him "even bigger, even better", hinting that he intended to take over the railway in his new form! Fortunately, Theo and Otto reversed the polarity of Excelsor 2 when Owen went inside, successfully reconfiguring him back to his original shunting diesel form. 

Strangely, with Owen back in his original form, his memories of the entire experiment had also mysteriously been wiped. Theo and Otto quickly knocked Owen out and returned him to Merecombe sheds, remaining there to monitor him once he awoke. When Owen did regain conciousness, he claimed to have had a nightmare involving him turning into a monstrous, larger, more powerful version of himself. With Ryan's help, Theo and Otto managed to convince Owen that it had all been a dream. Owen appeared satisfied with this, and, breathing a sigh of relief, Theo and Otto claimed "Excelsor 2" to be a success. 

Scared of Owen's reaction to being exposed to Excelsor 2's power changing abilities, however, Theo and Otto decomissioned the experimental machine, deeming it too dangerous in the wrong hands. However, the Excelsor 2 technology was later successfully miniaturised to become the "Tau Cannon", an experimental superweapon used by Theo and Otto "in case of emergencies".

Excelsor 3Edit

Teleporter original

Excelsor 3, as built.

Theo and Otto decided to use the shell of "Excelsor 2" to create a new machine, codenamed "Excelsor 3", which could, potentially, assist with operations around the railway. Having failed to successfully clone or reconfigure an engine, the twins decided to ask themselves a question: Could they cut out the need for locomotives at all? They argued that, if they could work out a way to transport goods, services and passengers without the need for locomotives, they would, theoretically, gain unlimited leisure time and not ever have to work again.

Spurred on by this, they began working on Excelsor 3, a "teleporter" working in a similar way to Excelsor 2, but instead of reconfguring something into a different shape, it could deconstruct, then reconstruct, such items in a different location, instantaniously.

Unfortunately, materials were becoming short in supply, so the twins convinced Dave, Brian and Raymond into retrieving some much needed materials for them from Radstock in Somerset. A contact had set them up with some important construction tools, minerals and a new power supply for the machine, whilst also providing a "set up" van to trick Dave, Brian and Raymond into thinking that the "materials" were some hot dogs, rusty old rails, and some rope, to avoid suspicion. Ironically, the rope and the rails would later be utilised into the construction of Excelsor 3 in various ways, whilst the hot dogs were given to their crews in exchange for their silence.

The twins continued working on Excelsor 3 throughout 1961 and 1962 in secret, scavanging materials wherever they could. During 1962, the twins began working on additions to the matrix to make it more flexible, including modules to "cure diseases in humans by eradicating corrupted cells within the body", "clone vital, none-living equipment for future experiments", and "a module to experiment with potentially delivering goods and materials before they had even been ordered". The last element was deemed "a time manipulating module" which was successfully tested, but not fully appropriated into Excelsor 3 due to the worries of changing the space time continuum. However, the coding remained intact within the machine, which would later lead to potentially disasterous consequences.

In early 1963, Excelsor 3 was almost ready, but there were some potential issues with the calculations. Fortunately for the twins, Brian's brother, "Brain", had recently arrived on the railway and, learning that he was a vastly intelligent engine, Theo and Otto kidnapped Brain and forced him to go over their calculations to see if they were correct and viable.

Brain indeed confirmed that their calculations were correct, bringing about the first successful test run of Excelsor 3, simply referred to as "The Teleporter" by Theo and Otto at this point. Brain became the machine's first test subject, with the engine being successfully dematerialised and rematerialised to a different, rather random, location. Reversing the polarity on Excelsor 3, the twins recalled Brain back to their lair, where he informed them of the sucessful test. Satisfied, but unwilling to allow Brain to share credit for the functioning machine, the twins activated Excelsor 3 once again, returning Brain to the island on which he was originally teleported to.

After this success, Theo and Otto decided to share "Excelsor 3" with "the wider scientific community, and the world".

The "Event Horizon" IncidentEdit

During the autumn of 1963, Theo and Otto invited their friends on the railway to view Excelsor 3's first "publicity test run". Unfortunately for them, only Dave, Brian and Raymond arrived, with the other engines fobbing them off with excuses. Mr Dark, who at this point had already recieved his teleportation wristwatch via time travel and had a vague idea about what was about to happen, wisely decided to stay away from the experiment.

Revealing their lair to their friends for the very first time, Theo and Otto prepared to show them that their "Teleportation technology" worked, by staging a test run, with Theo taking up position within Excelsor 3 to show them what the machine was capable of. Unfortunately, something catastrophic went wrong when the machine was fired up, causing an "Event Horizon" anomoly, which transported not only Theo, but Otto, Dave, Brian and Raymond, away from the railway.

Due to the "Time manipulation moule" activating during the experiment, the twins, plus their friends, found themselves, inexplicably, transported back in time to the year 1953, an unintended side effect of the module's activation. However, Excelsor 3's teleportation technology indeed worked perfectly, safely transporting the engines away from the Dark Railway, in Kent, to Carlisle, in the north.

Excelsor 3.5Edit

Teleporter 1953

Excelsor 3.5, as seen in 1953.

Whilst stranded in 1953 Carlisle, Theo and Otto beleived that they could create a duplicate of Excelsor 3, codenamed "Excelsor 3.5", as it would use the same technology to return them to their own time, and home to the Dark Railway. After weeks of searching and scavenging, the twins managed to construct a similar machine, capable of sending them back to where they belonged. They were helped by Hunter the Shunter during the construction process.

Unfortunately, they still needed to test it, but were confronted by Victor and Ludo before they could re-activate it. After a terrifying chase by the villains, Excelsor 3.5 was given a test run by Raymond, who sent Victor and Ludo through the machine, before returning them to discover wether the experiment was successful. Learning of it's success, the twins sent Victor and Ludo to their doom.

The following day, Excelsor 3.5 was activated again, and was used to transport Theo, Otto, Dave, Brian and Raymond back to the Dark Railway, and 1963. An algorithm installed within the machine's coding caused it to self destruct after they had all gone through, as a fail safe to prevent anybody else using it. It is unknown what happened to Excelsor 3.5 after the incident, but it was most likely recycled and turned into scrap.
Teleporter 1953 destroyed

The remains of Excelsor 3.5


Once returned to 1963, Theo and Otto decided to officially retire the "Excelsor 3" project, feeling that they had succeeded in their endeavours. However, keen to maintain some of the technology, the twins secretly constructed a wristwatch with the teleportation technology successfully miniaturised inside it. Deciding that Mr Dark would find it useful, they sent it back in time to 1959, where it appeared in Mr Dark's office at Merecombe, with a note of explaination.

Mr Dark occaisionally uses it to keep an eye on his engines, often using the technology to appear out of nowhere and scare his engines. However, as explained by Theo and Otto, the miniaturised technology limits the distance Mr Dark can travel whilst using it, and the amount of times he can use it, therefore, Mr Dark rarely relies on the watch for transportation.

After the incident, the twins discovered that their lair had been all but destroyed by Excelsor 3 in the resulting explosion after they had been teleported away from the line. Though they tried to clean it up and reuse it, the site was deemed unsafe, due to the risk that the entire site could collapse into the nearby ravine, and the twins abandoned it.

The remains of Excelsor 3, apparently, remains buried in rubble in their lair.

Theo and Otto are currently working on yet another machine, codenamed "Excelsor 4"...

Related TechnologyEdit

  • The Tau Cannon - utilising miniaturised technology from Excelsor 2
  • Mr Dark's wristwatch - utilising miniaturised technology from Excelsor 3


The Dark Railway Series


  • Excelsor 3 was never named in it's appearance in "Event Horizon", it was simply referred to as "The Teleporter" or "The Time Machine". It is likely that Theo and Otto did not want their friends knowing the code name for the project, in case they went digging for more information, or worse, jogged something in Owen's memory.
  • It is still unknown exactly how any of the "Excelsor" projects functioned.
  • Theo and Otto have never mentioned the projects by name.
  • Otto has secretly theorised that the "Excelsor 1" experiment actually did clone, or remove, part of Theo's soul, as, after the incident, Theo appeared to have lost some of his previous intellect and personailty. 
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