Saw the play in circa 1970s - absolutely brilliant - knew the famous family - the Purls from stage & screen, Americans who i met in Tokyo where I was on stage & TV acting unpaid apart from the TV! They knew Alan and in the 80s went to visit him in Whitby I believe.
I think Alan (was) the successor to Oscar Wilde, for which I have understudied a part for & did the costumes, both in NYC (whilst living in poverty) and costumes in Tokyo (whilst living in poverty for 3 years so much so that I didn't have a TV)!
Also know personally the famous actor Nick Lumley! Another great person from Yorkshire
Boom! Boom!