who is the main character in this film?
Uncle David (David Hoyle)
Uncle David
Late one night, Ashley (Ashley Ryder) – a young man with a childlike mentality – arrives at the caravan home of his Uncle David (David Hoyle) on the Isle of Sheppey. 
what is uncle david? British black comedy film
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Uncle David [SEP] Plot
He proceeds to give him a third and final injection, which he remarks will make Ashley lose consciousness and suffer organ failure. As Ashley dies, David professes that he has never loved anyone else as much before. The next morning, he goes onto the beach to place his nephew's body in a shallow grave, tearfully kissing the body goodbye before it is swept away by the sea.