Generally the main characters are George and Lennie, who are, as they are proud to proclaim, different from the others because they have each other. In fact, they are an odd couple, George the sensible, tough yet ultimately caring protector of the ironically named Lennie Small, who is in fact, a huge man who doesnt know his own strength and is mentally incapable of making the smallest of decisions for himself; he relies on George completely but equally, George needs Lennie as he gives him a reason to keep going. Lennie, despite his lack of intellect, senses this because when he knows George feels guilty for being angry with him, he takes advantage of the moment to manipulate George into repeating the story of their dream future, especially the rabbits they intend to keep with which Lennie is obsessed.
Interestingly, they arent related but Lennies aunt has brought up George and he has promised her that hell look after Lennie now she has died. A secret dream they share, of building a life together on a ranch and to liv off the fatta the lan is central but the very title of the book, from Robert Burns poem To a Mouse, foreshadows the ultimate defeat of their dream, since it speaks of plans going wrong.
These two men are on route for another in a series of ranch jobs, having run out of Weed, the place where they previously lived and worked, because Lennie has been wrongly accused of attempted rape because of his innocent desire to touch the material of a girls skirt; again there is foreshadowing here of the tragic ending of the novel. Indeed, the whole of the book follows the circular movement established by the setting of the beginning of the novel and inverting descriptions used there in the ending which takes place in the same spot, where Lennie has been warned to return if anything goes wrong which inevitably it does.
Upon arrival at the ranch, Steinbeck takes the opportunity to introduce the reader, via the newcomers, to an array of characters, all loners for one reason or another: the old, battered and dispirited Candy, the black, crippled and isolated Crooks, the feisty and arrogant bosss son, Curley, who is newly and unhappily married, his wife being what the others call a tramp, and the god-like Slim, to whom all the others look up and to whom they all look for an image to idolise. Steinbeck uses each of these in a different way to show twists of loneliness and isolation, with only Slim seemingly beyond the idea that he is an object of pity.
From the beginning, George is afraid that the aggressive bosss son, Curley, will cause trouble for himself and Lennie because he is an amateur boxer who sees Lennies size as a challenge and is handy. However, when he is involved in a violent incident with Curley through no fault of his own, Lennie crushes his hand and Slim warns him that if anything is said about it, he will make Curley look a fool, the thing he knows Curley fears most.
Indeed, Steinbeck continuously uses Slim as his centre of consciousness in the novel, the man in whom George confides. Slim is also the only one of the men who appears to have any kind of relationship with Crooks. It is no coincidence either, that it is Slim who comforts and consoles George at the end of the book, telling him You hadda, George. I swear you hadda and leading him away.
Perhaps the most controversial aspect of Steinbecks novel is undoubtedly his portrayal of women. The only female character to have a real presence in the book is Curleys wife, who appears to have married Curley on an impulse, having been disappointed in her ludicrous ambition to become a film star, and is already clearly on the lookout for a better prospect. She flirts with the men, is clearly attracted to Slim, and abuses Crooks, emphasising as she does this the racial tensions of the time. The other references to women are to prostitutes and Lennies late aunt, rather oddly sharing a name with the local madam. This way in which he portrays women could perhaps indicate difficulties in his personal life.
In conclusion, however, the appeal of Steinbecks powerful novel remains an extremely moving realisation of how deep the central relationship between George and Lennie is, and how their rather coincidental coming together becomes for both the defining emotion of their lives. Precisely because there are two of them, that someone, as George says, gives a damn, Steinbeck is able to highlight the loneliness of life in America at the time. The sharing of their dream with the desperate Candy is in a sense the beginning of the end because as it becomes almost a reality it is simultaneously broken by the intrusion of possibility symbolised by him. In Of Mice and Men, Steinbeck made a nationwide problem human and in doing so, he created characters who continue to both move and disturb.