Are you thinking of the film with the black detective named 'Shaft'?
Shaftesbury is actually a town in Dorset, England and (I presume) is where Shaftesbury Basses were manufactured.
And it's also the name of a road in central London (Shaftesbury Avenue) where Rose Morris, the distributors of the Shaftesbury brand, were situated.
Rose Morris sourced their Shaftesbury brand from all over the place - Japan, Korea, Italy, and yes England (though London rather than Dorset). They were probably sourced from whoever gave them the best deal at the time. Their Rickenfakers were Japanese, but nobody seems to have been able to identify exactly which factory.