Like many of Dickens' novels, The Pickwick Papers is quite hard to summarise. I'll do my best, though:
Mr Pickwick is a member (in fact, the founding member) of the Pickwick Club, an organisation dedicated, apparently, to "the cause of science", although this is never really corroborated. Anyway, Pickwick and three of his friends form a sort of sub-club, the Corresponding Society of the Pickwick Club, and go on various adventures throughout the country, meeting many different people and many different situations. As usual in Dickens, there seems to be no discernible storyline for the first half of the novel; but slowly, slowly, a shape and a reason emerges.
Talking of shape, the basic premise of the novel is that it is collated from various papers relating to the Pickwick Club and Corresponding Society by unknown "editors"; but this premise is contradicted and later mostly forgotten, as we become privy to private thoughts and conversations that the editors could never have known of. However, strangely, instead of ditching the form altogether, Dickens continues to include vignettes connected with the story only in that they were written on some mysterious piece of paper, or that some odd stranger related them. There is the story of Gabriel Grub, a prototype of A Christmas Carol ; "The Bagman's Story", which, I am convinced, inspired the ghostly post-office in Terry Pratchett's Going Postal ; and "The Convict's Return", which bears more than a passing resemblance to Tennyson's poem "Rizpah". Most of these stories are fairly harmless little interludes, but there's one that appears towards the end, interrupting the action and stopping the pace of the novel altogether.
Then there are the characters. The unscrupulous lawyers Dodson and Fogg form part of Dickens' crushing satire of the legal profession. The ill-fated Chancery prisoner in the Fleet debtors' prison provides the obligatory Pathetic Scene at End of Chapter. The dastardly Mr Jingle, the heavy-drinking medical students and the amiable Wardles all contribute to the picture of society that is built up in these pages. But it is the Wellers, Sam and Tony, who are the real joys of the piece. Surely Sam's loyalty to Mr Pickwick, his employer, inspired Samwise Gamgee in The Lord of the Rings : they share the same sort of unlearned wisdom. Sam Weller always knows what best to do, and how to treat the deceivers and social climbers of the world. Tony Weller, Sam's father, is a little more naive but still comes out with gems of wisdom like "It's a rum sort o' thing, Sammy, to go a hankerin' arter anybody's property, ven you're assistin' 'em in illness."
I think the most important thing about Pickwick , however, is how easy it is to read compared with Dickens' other novels. Often, when reading Dickens, I feel a kind of dread in picking it up and having to slog through it, but I never had such qualms with Pickwick . It's genuinely funny, too. So, although I didn't like the story as much as, e.g., Our Mutual Friend or Dombey and Son , I think I enjoyed the experience of reading it more. Go figure.