Little Dorrit was published in nineteen monthly instalments, each consisting of 32 pages with two illustrations by Hablot Knight Browne whose pen name was Phiz. Each instalment cost a shilling except for the last, a double issue which cost two shillings.I – December 1855 (chapters 1–4)
II – January 1856 (chapters 5–8)
III – February 1856 (chapters 9–11)
IV – March 1856 (chapters 12–14)
V – April 1856 (chapters 15–18)
VI – May 1856 (chapters 19–22)
VII – June 1856 (chapters 23–25)
VIII – July 1856 (chapters 26–29)
IX – August 1856 (chapters 30–32)
X – September 1856 (chapters 33–36)
XI – October 1856 (chapters 1–4)
XII – November 1856 (chapters 5–7)
XIII – December 1856 (chapters 8–11)
XIV – January 1857 (chapters 12–14)
XV – February 1857 (chapters 15–18)
XVI – March 1857 (chapters 19–22)
XVII – April 1857 (chapters 23–26)
XVIII – May 1857 (chapters 27–29)
XIX-XX – June 1857 (chapters 30–34)
The novel begins in Marseilles "thirty years ago" (i.e., c. 1826), with the notorious murderer Rigaud telling his cell mate how he killed his wife. Arthur Clennam is returning to London to see his mother after the death of his father, with whom he had lived for twenty years in China. On his deathbed, his father had given him a mysterious watch murmuring "Your mother," which Arthur naturally assumed was intended for Mrs. Clennam, whom he and everyone else believed to be his mother.
Inside the watch casing was an old silk paper with the initials DNF (Do Not Forget) worked into it in beads. It was a message, but when Arthur showed it to the harsh and implacable Mrs Clennam, a religious fanatic, she refused to tell him what it meant and the two become estranged.
In London, William Dorrit, imprisoned as a debtor, has been a resident of Marshalsea debtors' prison for so long that his three children – snobbish Fanny, idle Edward (known as Tip) and Amy (known as Little Dorrit) — have all grown up there, although they are free to pass in and out of the prison as they please. Little Dorrit, devoted to her father, has been supporting them both through her sewing.
Once in London, Arthur is reacquainted with his former fiancée Flora Finching, who is now overweight and simpering. His supposed mother, Mrs Clennam, though arthritic and wheelchair-bound, still runs the family business with the help of her servant Jeremiah Flintwinch and his downtrodden wife Affery. When Arthur learns that Mrs Clennam has employed Little Dorrit as a seamstress, showing her unusual kindness, he wonders whether the young girl might be connected with the mystery of the watch. Suspecting his mother was partially responsible for the misfortunes of the Dorrits, Arthur follows the girl to the Marshalsea. He vainly tries to inquire about William Dorrit's debt in the poorly run Circumlocution Office, assuming the role of benefactor towards Little Dorrit, her father, and her brother. While at the Circumlocution Office he meets the struggling inventor Daniel Doyce, whom he decides to help by going into business with him. The grateful Little Dorrit falls in love with Arthur, but Arthur fails to recognise Little Dorrit's interest. At last, aided by the indefatigable rent-collector Pancks, Arthur discovers that William Dorrit is the lost heir to a large fortune, finally enabling him to pay his way out of prison.
The newly freed Dorrit decides that they should tour Europe as a newly respectable family. They travel over the Alps and take up residence for a time in Venice, and finally in Rome, displaying an air of conceit over their new-found wealth (except for Little Dorrit). Eventually, after a spell of delirium, William Dorrit dies as does his distraught brother Frederick, a kind-hearted musician who has always stood by him. Little Dorrit, left alone, returns to London to stay with newly married Fanny and her husband, the foppish Edmund Sparkler.
The fraudulent dealings (similar to a Ponzi scheme) of Edmund Sparkler's stepfather, Mr. Merdle, end with Merdle's suicide and the collapse of his bank business, and with it the savings of both the Dorrits and Arthur Clennam. Clennam is now himself imprisoned in the Marshalsea, where he becomes ill and is nursed back to health by Amy. The French villain Rigaud, now in London, discovers that Mrs. Clennam has been hiding the fact that Arthur is not her real son, and tries to blackmail her. Arthur's biological mother was a beautiful young singer with whom his father had gone through some sort of non-legal marital ceremony, before being pressured by his wealthy uncle to marry the present Mrs. Clennam. The latter insisted on bringing up little Arthur and denying his mother the right to see him. Arthur's real mother died of grief at being separated from Arthur and his father; but Mr. Clennam's wealthy uncle, stung by remorse, had left a bequest to Arthur's biological mother and to "the youngest daughter of her patron," a kindly musician who had taught and befriended Arthur's real mother– and who happened to be Little Dorrit's paternal uncle, Frederick. As Frederick Dorrit had no daughter, the inheritance was to go to the youngest daughter of Frederick's younger brother, William; that is, to Little Dorrit.
Mrs. Clennam has been withholding her knowledge that Little Dorrit is the heiress to an enormous fortune and estate. Overcome by remorse, the old woman rises from her chair and totters out of her house to reveal the secret to Little Dorrit and beg her forgiveness, which the kind-hearted girl freely grants. Mrs. Clennam then falls in the street, never to recover the use of her speech or limbs, as the house of Clennam literally collapses before her eyes, killing Rigaud. Rather than hurt Arthur, Little Dorrit chooses not to reveal what she has learned even though this means forfeiting her legacy.
When Arthur's business partner Daniel Doyce returns from Russia a wealthy man, Arthur is released with his fortunes revived, and Arthur and Little Dorrit are married.
Like many of Dickens's novels, Little Dorrit contains numerous subplots. One subplot concerns Arthur Clennam's friends, the kind-hearted Meagles. They are upset when their daughter Pet marries an artist called Gowan, and when their servant and foster daughter Tattycoram is lured away from them to the sinister Miss Wade, an acquaintance of the criminal Rigaud. Miss Wade hates men, and it turns out she is the jilted sweetheart of Gowan.
The character Little Dorrit (Amy) was inspired by Mary Ann Cooper (née Mitton), whom Dickens sometimes visited along with her family, and called by that name. They lived in The Cedars, a house on Hatton Road west of London; its site is now under the east end of London Heathrow Airport.
Like much of Dickens' later fiction, this novel has seen many reversals of critical fortune. It has been shown to be a critique of HM Treasury and the blunders that led to the loss of life of 360 British soldiers at the Battle of Balaclava. Imprisonment – both literal and figurative – is a major theme of the novel, with Clennam and the Meagles quarantined in Marseilles, Rigaud jailed for murder, Mrs. Clennam confined to her house, the Dorrits imprisoned in the Marshalsea, and most of the characters trapped within the rigidly defined English social class structure of the time.
Tchaikovsky, a voracious reader and theatre-goer when he was not composing, was entranced by the book.
Little Dorrit has been adapted for the screen five times. The first three productions were in 1913, 1920, and 1934. The 1934 German adaptation, Kleine Dorrit, starred Anny Ondra as Little Dorrit and Mathias Wieman as Arthur Clennam. It was directed by Karel Lamač. The fourth adaptation, in 1988, was a UK feature film of the same title as the novel, directed by Christine Edzard and starring Alec Guinness as William Dorrit and Derek Jacobi as Arthur Clennam, supported by a cast of over 300 British actors.
The fifth adaptation was a TV series co-produced by the BBC and WGBH Boston, written by Andrew Davies and featuring Claire Foy (as Little Dorrit), Freema Agyeman (as Tattycoram), Bill Paterson (as Mr Meagles), Andy Serkis (as Rigaud/Blandois), Matthew Macfadyen (as Arthur Clennam), Tom Courtenay (as William Dorrit), Judy Parfitt (as Mrs Clennam), Arthur Darvill (as Edward 'Tip' Dorrit), Eddie Marsan as Pancks, Russell Tovey (as John Chivery), Janine Duvitski (as Mrs Meagles), James Fleet (as Frederick Dorrit), Ruth Jones (as Flora Finching), Eve Myles (as Maggy Plornish), Ron Cook (as Mr. Chivery) Anton Lesser (as Mr Merdle), Alun Armstrong (as Jeremiah/Ephraim Flintwinch), Sue Johnston (as Affery Flintwinch), Emma Pierson (as Fanny Dorrit), Robert Hardy (as Tite Barnacle), John Alderton (as Mr Casby), Amanda Redman (as Mrs Merdle). The series aired between October and December 2008 in the UK, in the USA on PBS's Masterpiece in April 2009, and in Australia, on ABC1 TV, in June and July 2010.
In 2001 BBC Radio 4 broadcast a radio adaptation of five hour-long episodes, starring Sir Ian McKellen as the narrator.
Little Dorrit forms the backdrop to Peter Ackroyd's debut novel, The Great Fire of London (1982).