Ah-ha!
"The Day of the Doctor."
Another Old Skool/New Series connection:
[Spoiler (click to open)]Yes, the Space-Time Telegraph(also known as the psionic beam) was given by the Fourth Doctor to the Brigadier (and of course that end of it wound up in the Black Archive). And it made its first appearance at the end of "The Revenge of the Cybermen," leading right into..."Terror of the Zygons!"
Also, I'm now a wee bit disappointed that no one said the line "Let Zygons be Zygons" during the treaty negotiations.
Another Old Skool/New Series connection:
[Spoiler (click to open)]Yes, the Space-Time Telegraph(also known as the psionic beam) was given by the Fourth Doctor to the Brigadier (and of course that end of it wound up in the Black Archive). And it made its first appearance at the end of "The Revenge of the Cybermen," leading right into..."Terror of the Zygons!"
Also, I'm now a wee bit disappointed that no one said the line "Let Zygons be Zygons" during the treaty negotiations.