The Second Doctor meets the Third Doctor
Gallifrey, the Time Lords homeworld, is under attack. Stuck on Earth in a strange energy field, Jo, the Doctor and Sergeant Benton are trapped inside the TARDIS unable to help. That is until the Time Lords decide to break the First Law of Time and let the Doctor help himself -- literally! Classic clip from The Three Doctors, first shown in 1973.
The Three Doctors Unite!
Upon seeing the bickering between the two Doctors, the Time Lords decide to send in more reinforcements -- this time in the shape of the First Doctor. Can he stop his successors from arguing long enough to figure out what is going on?