Heard of King Arthur have you? Fourth Century Celtic yahoo with a magic sword?

Actually it was a high tech tungsten steel sword with a vibrating blade and sunlight charged power cells, manufactured by the Royal and Imperial Workshop of London, England, in one of the many parallel Nineteen-forties.

The problem lay not in making the weapon but in getting it to Arthur. Bring in Time Travel. I hear you snigger. Time Travel? Ha, ha! Impossible. Actually it isn’t impossible, we all travel through time, even you, slowly, in a direction we think of as forward. Beyond that, what we call the future does not yet exist and cannot be jumped into.

The past, however, did exist and still does exist if you know how to reach it; and should you reach it you can also return to your starting time. All you need are the Time Equations, that esoteric mass of peculiar symbols conceived by a psychotic scientist. A small problem with the Time Equations, however, is that the values change slightly for any given continuum. Be aware. Be careful. You also need an enormous amount of power which presents no real problem, construct an enormous and hugely filthy nuclear power plant and shift it into hyperspace from where you can tap into it from any dimension. Given all that, how can you go wrong? Er, actually, it’s easy to go wrong. Think of a moody, suspicious, homicidal King Arthur XXII, and tremble. I have translated Merlin’s smudged, soup and ale stained, hand written account from the original Court Latin into modern English for you. Be grateful. Don’t blame me if you don’t believe it.