"No!" Nyssa shouted. "That's all the antilazar! It took us weeks to synthesize it!"
The Master raised the beaker to his lips.
"That's 500 doses, enough for everyone on Terminus!" the Doctor pleaded.
Ace tried self-interest. "You don't know what that will do to you!"
"Oh," slimed the Master, "but I do." He shot the beaker's contents like two fingers of whiskey, and had just enough time to set it down again before collapsing.
The Doctor, Ace and Nyssa converged on the body just in time to see a gelatinous mass seep out of it. The mass assumed the form of a cobra, hissed at them, and zipped out the door of Nyssa's office.
"How did he know?" The Doctor charged after it, Ace close behind. Nyssa would have followed, but she heard a groan from the body. She turned, and it was moving - and the color of its hair and beard was fading from black to white.
The eyes opened. "Nyssa? ... What has happened to me that you have aged so? Where are we?"
"Father?"
THE END