Often at this stage in the Reading Group cycle, when there is a film adaptation of the novel we're discussing, it's interesting to compare the two different art forms. You can learn a lot about what makes novels so special and interesting just from thinking about the compromises that have to be made to get all those words onto the screen. Likewise, a good film adaptation can also make you think about a book in a new way, just as a good actor can become the character who before was only a vague sketch in your head.

So I'd assumed that the hugely successful Academy Award-winning adaptation of To Kill a Mockingbird, starring the great Gregory Peck would provide plenty of good material. But now I've watched it, I have little to say. It's almost too obvious to point out that Gregory Peck is a good Atticus. He has just the right combination of gravitas and human warmth, just the right level of floppy-haired handsomeness to appear every bit as lovable and admirable as the man on the page. It doesn't hurt either to know that Peck was about the closest thing to Atticus Finch Hollywood has ever produced in real life too: the outspoken opponent of McCarthy, the critic of Vietnam, the enemy of Nixon. It's a cliche to say that this was the role he was born to play, but it doesn't make it any less true.

Otherwise, the film is such a faithful, and more importantly, effective rendition of the book that I didn't feel that there was much point watching it so soon after reading it. It's largely a compliment to the film that it all seemed to chime so well with Harper Lee's vision – except that it just felt like a rerun. If I wasn't so familiar with the text, I'm sure I'd have taken more from it. As it was, I found myself fixating on tiny variations. Like the fact that you see Boo Radley's father concreting in the hole in the tree where Boo had been leaving gifts for the children. This presumably happens "live" because it's very hard to do the visuals for a concreted-over hole in a black-and-white film. I know. In the greater scheme of things, or even the lesser, that isn't very interesting.

Talking of black and white, however, one thing did strike me. Much as I love watching actors like Gregory Peck in action, there was definitely an imbalance in the amount of screen time he got compared to Brock Peters. Who is Brock Peters, I hear you ask? He's the actor who plays Tom Robinson, the accused in the climactic court case. The fact that you've probably never heard of Peters, even though he too gives a fine performance, speaks volumes. (Although I would temper that slightly with the information that he's appeared in 125 titles, according to the IMDb. Clearly, his destiny was to be ranked among the "also including".)

It's also notable that until Peters appears on screen about 2/3 of the way through the film there are probably fewer than 10 words spoken by a black actor. Which could be seen as rather an oversight in a film about race relations …

This is an issue we've circled frequently this month on the Reading Group. How well does To Kill a Mockingbird really fit with its 1961 publication date? Did it help the Civil Rights movement? Or was its focus on the benevolent white paternalism of Atticus Finch actually a problem? Was it really possible to trust that the decent folk in Southern towns would eventually put their own house in order, as many say the novel suggests? Or did that position actually get in the way of the more radical Civil Rights movement and the reality that black people needed to take power and win freedoms for themselves? Well, the ultimate answer to all that is probably a copout. To Kill a Mockingbird is a novel and a very particular view of the world seen through the eyes of a very particular child. It isn't a prescription for setting US and world society to rights. The fact that some see the novel that way is a testament to its power – but the fact that it might not provide all the best solutions should not be seen as a weakness.

Mind you, here's a fascinating reading for those, like me, who may have tended to assume that Harper Lee's novel isn't especially radical. It comes from Reading group contributor Eric Wojcik:

"For me, one of the key scenes - in fact, one of the key passages in all of American literature - is when Atticus shoots the rabid dog on the street. It's organised partly as a throwaway, or at most a demonstration of Atticus's desire to protect his children, but at core it's a darkly resonant symbol of what, I believe, Harper Lee truly thought would be necessary to eliminate racism in the United States.
Tom Ewell is the rabid dog – there's no improving him, he does nothing constructive in the world. He was born in hatred, is hatred, and destroys. I believe Lee is placing this alongside the wider discussion of law, order, and extra-judicial responsibility, not as a socially legitimate alternative, but as a horrific shadow. Because the men and women around us are not dogs we can simply shoot down (if we wanted to; we are not monsters) before they ravage us with their hatred, we must try to battle using the relentless imperfections of law and civil society. And because we have to use these flawed systems, we will never be rid of the darkness in these people's souls.
To me – and I should say I'm American, and know the South pretty well – that's harrowing."

Harrowing is the word. If you doubt this interpretation, just look at the language that is applied to Ewell in the book. He is "trash", a "stinking carcass". He also dies in pretty much the same place as the dog mentioned by Eric Wojcik. Following that, Sheriff Tate gives him the following eulogy: "Mr Finch. there's just some kind of men you have to shoot before you can say hidy to 'em. Even then, they ain't worth the bullet it takes to shoot 'em. Ewell 'as one of 'em."

OK, it's possibly still an extreme view of the book. But it can't be ruled out entirely. If I've learned anything about To Kill a Mockingbird this month it is that it is open to all sorts of interpretations. It's full of ambiguity and, in spite of the adorable Scout, the noble Atticus and all that demonstration of human decency, it's full of darkness, danger and difficulty. It's a book you underestimate at your peril. And all the better for that.