Within this Hollow Crown

The part-observed anatomy of a man who, without question, is a revered local Glasgow Godfather. Well! That's what they all know this self-made man as.
We may judge his justified reasoning and that of his diverse cohorts as we observe their continuing operations from the city streets to behind the wall at 81, the avenue number of Barlinnie Prison.
The man himself is known to all by the name of 'Bulldog.' In 1968, there were 3,501,564 global births, including Andrew 'Bulldog' Drummond and Mr Chang Wie. The fusion of two can bear much fruit.
The first birth sound that was made by Andrew Drummond was a yell. Was it a warning? Or just telling us that he had arrived?