The Reckoning (1970)

Michael Marler, a successful business man in London, is about to make his way to the top. The death of his father brings him - after five years - back to his hometown Liverpool, where he is confronted with his lost Irish roots. He finds out that his father died because of a fight with some anglo-saxon teddy boys. It becomes "a matter of honour" for him, to take his revenge without involving the British police.