Dempsey's was a standalone brewery operating from Inchicore in the early 1980s. I came over to Ireland in 1983 to help set up Harty's brewery in Blessington, Co. Wicklow with Oliver Hughes and Liam LaHart (nowadays of Porterhouse fame). Shortly afterwards the Dempsey's brewer left, so I was working on secondment there. Dempsey's was owned originally by Liam O'Dwyer of O'Dwyer's of Mount Street and a few other investors; O'Dwyer bought the others out in 83/84. I left Harty's in 84 and joined Dempsey's as brewer. Beer brewed was the real ale described by Bamberger. Sales were not good, as the concept was 10/15 years ahead of its time, so we tweaked the recipe slightly, exported the beer in a tanker truck to Greenall Whitely in England, where it was bottled and sent to America.
To cut a long story short, the American importer turned out to be a crook, and didn't pay Dempsey's for the beer received. It went to the American courts, but due to no cash flow, the brewery closed its doors in I think 1985. Coincidentally, DEMPSEY bought the defunct brewery to set up his own (Fox's), but never got into production. But he can tell the story of the later part.