IC: A Mysterious Chamber
"Since you asked so nicely," the voice purred, and another sphere of light appeared. It shone some distance away, and higher up, as if the speaker was on a balcony overlooking the captives. He was dressed in black, with a very tell-tale beard, and piercing eyes. "I am the Master. I am the Master, and you will... probably try to disobey me. I do not advise it, as I have brought you here in order to save your lives."
"It appears that you have already handled some of the introductions. But please indulge me. Let me clarify exactly who you are, so your new friends can better understand what is going to happen to you." He produced some form of remote control device from somewhere, and pressed it. At once, a larger-than-life sized holographic image appeared - and it displayed selected excerpts from the life of River Song. Apparently they were specific memories. Someone had used a mind probe. It did explain why the four captives had headaches...
"Doctor River Song. Archaeologist. Adventurer. Soldier of Fortune, for the right reasons, and professional miscreant, for the right price. Criminal record is quite breathtakingly expansive. To summarise; theft, fraud, confidence trickery, tomb robbing, bigamy, trigamy, possibly quadrigamy - you really do need to remember to divorce before marrying again, you know. Temporal chicainery on a grand scale. And then there's the problem you have with murder. You're supposed to not get caught when you do that. But perhaps you enjoy escaping from prisons. You seem to have that habit. And while your historical skills are useful, your ability to manipulate social situations, and shoot people in the head, are of more use to me now than any other little quirks you may have developed."
A flick of the wrist, and the Brigadier's life was exposed for all to see. "Brigadier Alistair Gordon Lethbridge-Stewart..." The Master seemed to taste the words with a degree of glee. "At last the tables have been turned! I am sure you are not remotely enjoying your captivity. Perhaps it will help you develop some empathy, next time you try to place me into a cell. As everyone can see, your life has been one tedious stream of service and self-sacrifice, interspersed with moments of idiocy, and the occasional minor attempt at genocide of any creature that you don't particularly like the look of. How the Doctor could stand to be around you for so long is quite beyond my comprehension. But for once, you can put your determination to solve every problem with a bullet to the head to some constructive use. Believe me, you will have plenty of opportunities to shoot some aliens, since that is what you apparently do best. And yes, your bullets will actually be effective. On some of them. Possibly."
The image changed again, and the holographic cinema played the Life and Times of Zoe Heriot, Girl Genius. "Zoe Heriot. What can I say? Towering intellect, eidetic memory, a stream of degrees that quite beggars the imagination, and a personality so smug and annoying that it is a miracle that you were not strangled at birth. Fortunately for me, you somehow managed to avoid being pushed out of an airlock by your colleagues. I am going to give you every chance to demonstrate your intelligence, young lady, and I do hope you are up to snuff, or you're going to die a particularly ignominious death. Such a shame."
Finally, the large hologram becomes the life of Sarah Jane Smith. "Sarah Jane Smith! What an honour it is to meet you at last... except, of course, you have already met me in the future, if your memory is correct. How curious. Journalist, dear friend of my own dear enemy, and future saviour of the planet Earth. Oh yes... as Doctor Song might say... Spoilers. As it happens, your presence here is not essential. You do not bring very much to the party, as it were, but I had the temporal vortex, and I thought to myself... why not? I expect you are here mostly as cannon fodder. Chances are at least one of you will die, and I decided to choose someone whose demise would cause the greatest amount of damage to that aggravating little bauble you call home. I am so very sorry about that. Do try not to die immediately, it would be rather a disappointment."
The images faded, and his manner became rather less smug and derisive. "Now tell me... Doctor Song, what do you know about Azforth Krenzac, and his infamous Challenge?"