A British Airways Concord disappears on final approach. The Doctor, still reeling from the loss of Adric, becomes involved when his TARDIS miss-fires from its intended destination of London 1851 and appears at Heathrow airport. The Doctor follows the lost plane into the deep past only to discover he is part of an illusion. This forces him to ask the question: if there is an illusion, who is the conjurer? Written by
Did You Know?
This is considered by fans to be the worst story of Peter Davison's run, an opinion shared by the actor himself. He claimed it was a "very good story, but we had run out of money. We filmed the prehistoric landscape of Heathrow airport in Studio 8 [at TV Centre] with a model Concorde in the back of the studio. The monsters were bits of foam. We didn't do the story justice." See more
Behind every illusion there's a conjurer. In this case I shouldn't think he went to all this trouble for our entertainment.