I'd considered... then discounted... both Enemy At The Door and Island At War, since these were both Channel Islands occupation dramas. The Fourth Arm looks like a possible candidate but all I can find of it on YouTube is a trailer which doesn't feature the opening or end credits
It doesn't appear to have been released on DVD either... I can't find it on Ebay... but thanks for you input, guys (it wasn't Dr Who either, Onkel Neal

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