The Doctor's past incarnations are taken out of time by a forbidden time scoop device. The fourth Doctor becomes trapped in the vortex but the others find themselves, together with a number of their old companions, with the fifth Doctor and his companions in the Death Zone on their home planet Gallifrey. Here they face a Dalek, a Yeti, a quicksilver Raston Warrior Robot and numerous Cybermen. Also present is the Master, who has been summoned by the High Council of Time Lords to help the Doctor. It turns out that President Borusa is the mysterious operator of the time scoop. He aims to use the Doctors to breach the defences of the Dark Tower--Rassilon's tomb--so that he can enter there and claim immortality. When he does so, however, he is condemned by Rassilon to eternal existence in the form of a living statue.
Yes, "The Five Doctors" is the one that gathers together Hartnell, Troughton, Pertwee, Baker, and Davison, dumps them on some moorland, and lets some of the Doctor's greatest enemies take potshots at them. Except, of course, William Hartnell had passed on by the time this series was made in 1983 (although his replacement Richard Hurndall does an excellent job), and Tom Baker was only featured as a patched-in cameo, apparently prevented from joining in by a temporal thingummy. However, this kind of creakiness comes with the territory and is soon forgotten. The assorted incarnations of the Doctor (together with a scattering of assistants) are drawn together through time and space to battle Daleks, Cybermen, Yeti--those weird androids that keep jumping into the air and disappearing--and many other old foes. They realize that they're on their home planet of Gallifrey and must eventually deal with the legacy of Rassilon, founder of the Time Lords. --Roger Thomas