This is a low budget revenge / vigilante thriller - but quite well done, of its type.
The story goes something like this: Joe is a shy and retiring young man whose outgoing older brother John seems to be his best - and only - friend. After a minor altercation John is killed in a fight outside a pub. Joe mooches in his room until a knock on the door reveals Piggy, claiming to be an old friend of his brother. Piggy is a hard man, direct and brutal, and involves Joe in violent revenge on the yobs responsible for his brother's death. Err, that's it...
But is Piggy real or fantasy? Is it a tale of Joe's solitary descent into violence as he broods on how a weakling could get revenge? That's up to the viewer - but suffice to say that for a low budget film it's very well acted, the dialogue is good, and the locations are realistic. I enjoyed it (can one 'enjoy' a violent, brutal revenge film? - but you know what I mean...).
I'll give it 4/5 stars, although that may be a little high.
[Aside: the film appears to be set around Camden / Chalk Farm / Kentish Town, although the pub scene was filmed in the 'Prince Of Wales' in Mottingham Road, SE London - if locals don't mind me describing Mottingham as in SE London!]