Had the Brigadier's attention not been elsewhere at the time, he might never had walked into the trap. Not that we can blame him, for it was certainly a very clever trap. Not only that, but he was still a little exhausted having just returned from a UNIT conference in Ottawa.
While sitting in his office, sipping coffee and wearily going through the contents of the 'in-tray', he received a call on the orange telephone. Internal calls were orange and this one came from the laboratory; the Doctor's voice was at the end of the line.
'Lethbridge-Stewart? Come straight along to the lab, old chap. Got something to show you. Splendid new device I've just done inventing - ought to give us a warning each time the Master's TARDIS arrives on this little planet of yours!'
Now, this was just too good to be true. So, off he trotted to the lab whereupon he was greeted by the Doctor who then declared that his new gizmo was inside his TARDIS.
'Follow me, old chap,' said the Doctor, leading the way into the unique Police Box.
Unfortunately, the Brigadier did not realise until it was too late that it was not in fact the Doctor's TARDIS that he was walking into! Oh yes - it looked like a Police Box all right, but a shiny new one with white window-frames and a St. John's Ambulance symbol on the door; Dr. Who's TARDIS hadn't looked like that for quite some time now.
Meanwhile, the real TARDIS - belonging to the real Doctor - had just materialised in the depths of a rather cindery world in the outer solar-system. Why do we find Dr. Who here? Well, we must go back a few hours or so to the late evening of the previous day - Sunday - where we find Sgt. Benton on security duty: eating corned-beef sandwiches and watching TV in the Brigadier's quarters...
'And now no BBC3,' said the announcer as a spinning model of the planet Earth filled the screen, 'we take our monthly gaze at the heavens as Patrick Heath shows us "The Sky About Us" '.
Next door in the lab, the Doctor was pushing up "z's" in the depths of the TARDIS, the doors of which were wide open for it was a hot night and the TARDIS air-conditioning was on the
blink. Benton sat back at the sound of the Doctor's snoring was deadened by the grave theme music of the astronomy TV show. The Doctor was in the middle - or, to be exact, one third of the way into - a dream that he was in Florida with some friends of his who just happened to be manatees when he was at once awoken by the foreboding 'Bong!' of the cloister-bell. What could it be this time?
This Patrick Heath was no mug, thought Benton. Apparently, he could play the glockenspiel too! No mean feat. All of a sudden, the door was thrown open - there stood the Doc in night-shirt and tasselled night-cap like Marley's ghost! He was staring blankly at the TV his eyes wide as though they were on the point of vacating their sockets and scarpering on fear. Inside the Doctor's head, the ominous cloister-bell was bonging away.
'You okay, Doc?' said Benton. He received no reply, and uneasily followed the direction of the Doctor's gaze to the TV set.
'Tonight, viewers,' Heath was explaining, 'we are going to have a chat with the American cosmologist Carl Burke who has some interesting news to pass on from Voyager X - a new planet at the edge of the solar-system!!!'
The ringing suddenly stopped.
'Why, yes - of course!' mumbled the Doctor. 'Of course...I should have known.' He blinked, cleared his throat, and returned to the TARDIS to resume his kip.
Now, this shook Benton up a bit, so he took another munch of his sandwich and washed it down with a swift gulp of cocoa. On the TV, Carl Burke was showing Patrick Heath a scale-model of Voyager X. What a bunch of cobblers, thought Benton. It looked like something they'd build on 'Blue Peter'. How could two grown men sit there and talk seriously about an old egg-box covered in tin-foil?
Next morning - just an hour or so before the Brigadier walked into the trap - the Doctor's fears were compounded when he received a visit from his former assistant / companion Liz Shaw. Before too long, the couple had taken off in the TARDIS, bound for the dark depths of the mysterious little world...
Within his space-time vehicle, the Doctor was relating to Liz his previous experience with the gloomy world beyond the safety of the TARDIS doors. He told her of how his age-old enemy, the Master, had used a Time-Scoop to redirect a NASA space-probe into the past and enjoy it in establishing himself as deity amongst the humanoid life forms on this planet; and of how the Master had been thwarted in this by the dreaded Daleks whom he had, and the Doctor, finally destroyed with a torpedo originally bound for Earth. He remembered one particular conversation he had had at the time with his old foe:
'My, my - tut-tut. You have come down in the Universe, haven't you? Working for the Daleks...You ought to rename yourself "the Servant"!'
The Doctor's companion Jo Grant shook in her kinky-boots as the Master's blood vessels swelled with barely-controlled rage as he fixed the Doctor with a devilish glare and replied, through clenched teeth, 'And you should be "the Nurse"! Doctor, I cannot reveal the extent of the Daleks' involvement in my master-plan, but I beg you to consider joining with me. We could achieve such greatness united. After all, we were comrades...once.'
Comrades...yes, they had been good friends at one time, in the innocent days of youth, centuries ago; united they had been then in rebellious curiosity, and in their mutual desire to break the Laws of the Time Lords and roam the great galaxies of the Universe - but in motivation alone did they differ...
'Join forces, with you?' the Doctor replied in indignant amazement. 'Subjugate all intelligent life in the Cosmos to your tyranny. Never! Never!! Never!!!'
'Heh, heh, heh,' cackled the Master through his greying goat's beard.'The cosmic-policeman in his cosmic police-box. So be it, my dear Doctor. So be it!!'
The planet's name was Nivkel, and the Doctor was not glad to be back...
The Master was a somewhat smaller man the Doctor, so the wig, cape, frilly shirt and smoking jacket that now the villain doffed were clearly mere accessories of some potent hypnotism with which the Brig had been duped.
Our military hero now stood secured to one wall of the Master's TARDIS with a magnetic clamp around each limb. Rendered helpless, he watched as Earth's most persistent foe threw the switch that would send his TARDIS into flight. But whither were they bound?
In an underground cave on Nivkel, an oblong block of light was cast in the pitchy gloom as the doors of the Doctor's TARDIS opened and he and his companion - both wearing oxygen-helmets the likeness of goldfish-bowls, stepped forth. At once, the beam from the Doctor's torch discovered something tat resembled one of the Viking probes that had landed on Mars in the 1970's. However, this probe differed in that it could, when functional, move around on six hydraulic legs. This was what they had come to look for. Liz had sought the Doctor's help after her work with Carl Burke on the Voyager project had resulted in a rather puzzling discovery: about to leave the solar-system, Voyager X had detected some radiation, presumably from a laser-beam! Thus had NASA come across this new world - but what, they wondered, and sent the signal? The Doctor had at once deduced its source and whisked her off there and then, eager to show off his now fully-functioning TARDIS.
'What is it, Doctor?' asked Liz. She was still a little flabbergasted that the TARDIS did work after all - and now here she was inside another planet!
'This, my dear Liz, is the space-probe sent from Earth to Nivkel in 1997,' he explained.
'1997? Oh come on, Doctor, it's only 198_!'
'Correct, Miss Shaw. But as I said, the Master sent the thing back in time - remember? In fact, this probe had been here for 500 years now - a credit to the people who built it, don't y' think?'
A credit indeed, Doctor: powered by its own nuclear-reactor, this descendant of Voyager X had been attempting to contact Earth since the fifteenth century with an infra-red signal. The Doctor now attempted to switch the signal off with his sonic-screwdriver, least any undesirable space-aliens should pick it up too. However, he was already too late! Yes - a spaceship full of very desirable aliens had already arrived on Nivkel, and one of them was watching the couple at that very moment!!