Q.E.D. (1982)

Once upon a Time by Michael Baker (1990x7)

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Every day Charles Tempus catches the 8.10 train to work; regular as clockwork. One morning a boy approaches him on the station platform and asks him the time. That innocent question takes Mr Tempus on a fascinating journey through time - back down the centuries in the days before clocks, and forward into the future via a black hole. On the way Mr Tempus meets young Albert Einstein who introduces him to the mysteries of relativity