It is almost impossible to give the plot of the novel. Sterne deliberately wrote it in such a way as to make it a continuos source of surprise for the reader. There is really no story only a sequel of scenes such as Walter Shandy (Tristam's father) talking with his brother Toby or with Dott. Slop,the country doctor. Such scenes cover several chapters due to e fact that the narrator interrupts the dialogue to digress in asides, flasback, long quotations from unknown books etc. Tristam Shandy is the "hero" of the novel, but he plays little part in the action; he is not even born until book IV and never get beyond infancy. Sterne deliberately avoids giving us a tradictional story tha follows the hero from youth to old age, describing his adventures. The bulk of the novel is taken up with odd stories and pages of comment on eccentric ideas.What stands out in the reader's mind, in fact, is the collection of eccentric characters that people it.Each of them is prisoner of his/her own fanciful world of mental associations and fixed ideas:"hobby-horses", as Sterne calls them.
Each man has a hobby-horse of his own:Toby Shandy measures everything around him according to military science. Walter Shandy is obsessed with proper names and people's noses;others with religious books, breeches, and so on.