I remember this one truly messing with my mind when I was a kid. Intriguing idea to have no segue at all between "dream" and "reality"...but unfortunately I think the lack of explanation, though it does raise the suspense level, also tends to raise a lot of (unanswered) questions. At any rate, I can see why this one has stuck with me through the years!...very vivid indeed. And more than slightly reminiscent of the show Nowhere Man.