Trying once more to return Tegan to Heathrow Airport, the Doctor instead lands the Tardis in the same location three hundred years earlier where he and his companions are chased by angry villagers but rescued by a charismatic highwayman.
The TARDIS returns Tegan to Heathrow Airport: Tall trees, peaceful, clear skies, thriving vegetation and a touch of sulfur in the air. Obviously the TARDIS is a little out of date (about three hundred years or so), but upon looking around the Doctor finds there's more amiss than his navigational controls, all arising after a recent comet crash that was not on Earth's schedule.—statmanjeff