In 1983 the Doctor is once again reunited with his old friend Brigadier Lethbridge-Stewart, only the Brigadier struggles to remember his adventures with the Doctor. Meanwhile Tegan also meets the Brigadier in 1977.
The TARDIS lands on Earth six years out of date, stranding the Doctor in 1983 while leaving Tegan and Nyssa to look for him in 1977, eventually to discover a badly injured man that may very well be the Doctor. Both parties also encounter former Doctor-companion Brigadier Lethbridge-Stewart, though in 1983 he curiously has no memory of the Doctor at all.—statmanjeff