Peter Boyle plays the working class man who comes later into the picture than Dennis Patrick, but the film is very much about both of their stories. Boyle plays the titular Joe who we first meet in a bar that Bill runs into after having killed a man. We meet Joe in the middle of a tirade about everything that he hates from politics, to race, to young people, to music, he pretty much hates everything. Boyle handles this scene while conveying the casual discontent he has. Boyle shows that Joe is very much ticked off and the anger is real, but Boyle says every line as if Joe has been saying it his whole life and he is. In the scene Boyle is just a bit much, but a bit much in a wholly natural fashion to the character of Joe.
Boyle importantly tones it down when we meet Joe in his day to day life showing properly that his bar rant was what he does at the bar with a few drinks in him. Boyle is effective in making Joe a well average Joe the rest of the time. He is rather genuine with his wife and at home. Boyle does not make him a great guy by any means but he does not have that intensity in the bar, and shows him to be a man who is able to function in his day to day time with even a certain charm. Boyle importantly in these scenes shows there nothing all that special about Joe making him a man who does seem to take his life in stride most of the time, even if there is always that barroom Joe within him.
The film takes a turn when Joe figures out that Bill murdered a man and decides to meet with him, not to blackmail him but rather to merely meet a man who has done something that he always talks about. Boyle has an effective chemistry with Patrick. They both have a certain nervousness and disconnect in regards to their differing social perspective, but where they connect is their connection of a hatred. What I like is that neither overplay this hate, keeping it the underlying tissue of their friendship, but still making it obviously what keeps the two together as they always keep their social disconnect a very strong factor between them throughout.
The film eventually follows them into the world of the young people which they hate, but they eventually embrace. This whole section of the film does feel somewhat contrived, but Boyle does well with these scenes nevertheless. Boyle once again calls back onto Joe as just a normal man when you get right down to it. He is very good in giving Joe just standard needs for a man that leads him into trying just about everything that he hates. Although the film does portrays it as far too swift of a transition, Boyle realizes the very human elements in the situation as something believable drives Joe to this behavior, something that Dennis Patrick fails to do.
Joe and Bill's fall into the antics of though is swift, but just as swift is the violent of the film when Joe and Bill go after the property the hippies stole from them. Boyle is good in this scene as he reverts to the barroom Joe, and it is is believable because Boyle established this side to Joe so well in that first scene. It does not quite carry the impact it should though mostly because of how instant it is. Yes it's trying to be jarring by how fast it is, but in doing so it does not make the ending as powerful as it could have it was a little more character based. Boyle still is solid in his performance at the end, as he is throughout his performance, but the way the film ends fails to realize the full potential of this performance.