William Wilkie Collins (8 January 1824 – 23 September 1889) was an English novelist, playwright, and author of short stories. He was very popular during the Victorian era and wrote 30 novels, more than 60 short stories, 14 plays, and more than 100 nonfiction essays. His best-known works are The Woman in White, The Moonstone, Armadale, and No Name.

Collins was a lifelong friend of Charles Dickens. A number of Collins's works were first published in Dickens's journals All the Year Round and Household Words. The two collaborated on several dramatic and fictional works, and some of Collins's plays were performed by Dickens's acting company.

Collins predicted the deterrence concept of mutually assured destruction that defined the Cold War nuclear era. Writing at the time of the Franco-Prussian War in 1870 he stated, "I begin to believe in only one civilising influence—the discovery one of these days of a destructive agent so terrible that War shall mean annihilation and men's fears will force them to keep the peace."

Collins was born at 11 New Cavendish Street, Marylebone, London, the son of a well-known Royal Academician landscape artist, William Collins. Named after his father, he swiftly became known by his second name (which honoured his godfather, David Wilkie). The family moved to Pond Street, Hampstead, in 1826. In 1828 Collins's brother Charles Allston Collins was born. Between 1829 and 1830, the Collins family moved twice, first to Hampstead Square and then to Porchester Terrace, Bayswater. In 1835 Collins began attending school at the Maida Vale academy.

From 1836 to 1838 he lived with his parents in Italy and France, which made a great impression on him. From 1838 to 1840 he attended Mr. Cole's private boarding school in Highbury. At this school he was bullied by a boy who would force Collins to tell him a story before allowing him to go to sleep. "It was this brute who first awakened in me, his poor little victim, a power of which but for him I might never have been aware...When I left school I continued story telling for my own pleasure", Collins later said.

In 1840 the family moved to 85 Oxford Terrace, Bayswater. In 1841 he left school and was apprenticed as a clerk to the firm of tea merchants Antrobus & Co. Collins's first story "The Last Stage Coachman" was published in the Illuminated Magazine in August 1843. In 1844 he traveled to Paris with Charles Ward. That same year he wrote his first novel, Iolani, or Tahiti as It Was; a Romance. In 1845 Iolani was submitted to Chapman and Hall, but it was rejected. The novel went unpublished during his lifetime. Collins said of the novel: "My youthful imagination ran riot among the noble savages, in scenes which caused the respectable British publisher to declare that it was impossible to put his name on the title page of such a novel." It was during the writing of this novel that Collins's father first learned that his assumptions that Wilkie would follow him in becoming a painter were mistaken.

In 1846 he entered Lincoln's Inn to study law on the initiative of his father who wanted him to have a steady income. After his father's death in 1847, Collins produced his first published book, Memoirs of the Life of William Collins, Esq., R.A., published in 1848. The family moved to 38 Blandford Square soon after, where they used their drawing room for amateur theatricals. In 1849 Collins exhibited a painting, "The Smugglers' Retreat", at the Royal Academy summer exhibition. His novel, Antonina, or the Fall of Rome was published by Richard Bentley in February, 1850. Collins went on a walking tour of Cornwall with artist Henry Brandling in July and August 1850. Collins managed to complete his legal studies, and was finally called to the bar in 1851. Though he never formally practiced law, he used his legal knowledge in many of his novels.

An instrumental event in Collins's career occurred in March 1851, when he was introduced to Charles Dickens by a mutual friend, the painter Augustus Egg. They became lifelong friends and collaborators. In May of that year Collins acted with Dickens in Edward Bulwer-Lytton's play Not So Bad As We Seem. Collins's story "A Terribly Strange Bed", his first contribution to Household Words, appeared in April, 1852. In May 1852 he went on tour with Dickens's company of amateur actors. Collins's novel Basil was published by Bentley in November. He stayed with Dickens in Boulogne from July to September, 1853, afterwards touring Switzerland and Italy with Dickens and Augustus Egg from October to December. Collins published his novel Hide and Seek in June 1854.

During this period Collins extended the variety of his writing, publishing articles in George Henry Lewes's paper The Leader, short stories and essays for Bently's Miscellany, dramatic criticism, and the travel book Rambles Beyond Railways. His first play, The Lighthouse was performed by Dickens's theatrical company at Tavistock House in 1855. His first collection of short stories, After Dark, was published by Smith, Elder in February 1856. His novel A Rogue's Life was serialised in Household Words in March 1856. He joined the staff of Household Words in October 1856. In 1857 his play The Frozen Deep was performed by Dickens's company. Collins's novel The Dead Secret was serialised in Household Words from January to June 1857 and published in volume form by Bradbury & Evans. Collins's play The Lighthouse was performed at the Olympic Theatre in August. The Lazy Tour of Two Idle Apprentices, based on Dickens's and Collins's walking tour in the north of England was serialised in Household Words in October 1857.

In 1859 Collins began living with Caroline Graves and her daughter. Caroline came from a humble family, having married young, had a child, and been widowed. Collins put Caroline down as his wife in the census of 1861, though they were never married. His collection of short stories The Queen of Hearts was published in October 1859. His novel The Woman in White was serialised in All the Year Round from November to August 1860. In 1861 he visited Whitby in North Yorkshire with Caroline Graves. He resigned from the staff of All the Year Round in January 1862. He began to suffer seriously from rheumatic gout in 1862. His novel No Name was serialised in All the Year Round from March to January 1863. At the beginning of 1863 he travelled to German spas and Italy for his health with Caroline Graves. His novel Armadale was serialised in the Cornhill Magazine from November to June 1866. His play No Thoroughfare, co-written with Dickens, was published as the 1867 Christmas number of All the Year Round, and dramatised at the Adelphi Theatre on December 26.

His search for background information for Armadale took him to the Norfolk Broads and the small village of Winterton-on-Sea. Here he first met and began a liaison with Martha Rudd, a 19-year-old girl from a large poor family. A few years later she moved to London to be closer to him. His novel The Moonstone was serialised in All the Year Round from January to August 1868. His mother, Harriet Collins, died that same year. During his writing of The Moonstone, while he was suffering an attack of acute gout, Caroline left him and married a younger man named Joseph Clow. Caroline had wanted to marry Collins, but he had resisted. Collins began using opium at this time for his gout pain, an addiction that lasted for the rest of his life.

Collins's and Martha Rudds's daughter Marian was born in 1869. After two years of marriage, Caroline left her husband and returned to Collins. Collins divided his time between Caroline, who lived with him at his home in Gloucester Place, and Martha who was nearby. When he was with Martha he assumed the name William Dawson, and she and their children used the last name of Dawson themselves. This arrangement continued for the rest of Collins's life. In 1870 his novel Man and Wife was published. This year also saw the death of Charles Dickens. Collins's second daughter with Martha Rudd, Harriet Constance was born in 1871. The Woman in White was dramatised and produced at the Olympic theatre in October 1871. His novel Poor Miss Finch was serialised in Cassell's Magazine from October to March 1872. His short novel Miss or Mrs? was published in the 1872 Christmas number of the Graphic. His novel The New Magdalen was serialised from October 1872 to July 1873. His younger brother Charles Allston Collins died later in 1873. Charles had married Dickens's younger daughter, Kate. Collins also advised Dickens's sister-in-law, Georgina Hogarth, when she was editing The Letters of Charles Dickens from 1833 to 1870 (published in 1880), with Dickens's daughter Mary Dickens.

In 1874 Collins toured The United States and Canada giving readings of his work. Collins's and Martha Rudd's son, William Charles, was born in 1874. His novel The Law and the Lady was serialised in the Graphic from September to March 1875. His short novel The Haunted Hotel was serialised from June to November 1878. His later novels include Jezebel's Daughter (1880), The Black Robe (1881), Heart and Science (1883), and The Evil Genius (1886). In 1884 Collins was elected Vice-President of the Society of Authors, founded by his friend and fellow novelist Walter Besant.

Collins died on September 23, 1889, at 82 Wimpole Street, following a paralytic stroke. He is buried in Kensal Green Cemetery, West London. His grave marker describes him as the author of The Woman in White. Caroline Graves died in 1895 and was buried with Collins. Martha Rudd died in 1919. Collins's last novel Blind Love, left unfinished at his death, was finished and published by Walter Besant in 1890.

Collins's works were classified at the time as "sensation novels", a genre seen nowadays as the precursor to detective and suspense fiction. He also wrote penetratingly on the plight of women and on the social and domestic issues of his time. For example, his 1854 Hide and Seek contained one of the first portrayals of a deaf character in English literature. As did many writers of his time, Collins published most of his novels as serials in magazines such as Dickens's All the Year Round and was known as a master of the form, creating just the right degree of suspense to keep his audience reading from week to week. Sales of All the Year Round increased when The Woman in White followed A Tale of Two Cities.

Collins enjoyed ten years of great success following publication of The Woman in White in 1859. His next novel, No Name combined social commentary – the absurdity of the law as it applied to children of unmarried parents (see Illegitimacy in fiction) – with a densely plotted revenge thriller. Armadale, the first and only of Collins's major novels of the 1860s to be serialised in a magazine other than All the Year Round, provoked strong criticism, generally centred upon its transgressive villainess Lydia Gwilt; and provoked in part by Collins's typically confrontational preface. The novel was simultaneously a financial coup for its author and a comparative commercial failure: the sum paid by Cornhill for the serialisation rights was exceptional, eclipsing by a substantial margin the prices paid for the vast majority of similar novels, yet the novel failed to recoup its publisher's investment. The Moonstone, published in 1868, and the last novel of what is generally regarded as the most successful decade of its author's career, was, despite a somewhat cool reception from both Dickens and the critics, a significant return to form and reestablished the market value of an author whose success in the competitive Victorian literary marketplace had been gradually waning in the wake of his first "masterpiece". Viewed by many to represent the advent of the detective story within the tradition of the English novel, The Moonstone remains one of Collins's most critically acclaimed productions, identified by T. S. Eliot as "the first, the longest, and the best of modern English detective novels...in a genre invented by Collins and not by Poe", and Dorothy L. Sayers referred to it as "probably the very finest detective story ever written".

Various factors (most often cited are the death of Dickens in 1870 and thus the loss of his literary mentoring; Collins's increased dependence upon laudanum; and a somewhat ill-advised penchant for using his fiction to rail against social injustices) appear to have led to a decline in the two decades following the success of his sensation novels of the 1860s. His novels and novellas of the 1870s and 1880s, while by no means entirely devoid of merit or literary interest, are generally regarded as inferior to his previous productions and receive comparatively little critical attention today.

The Woman in White and The Moonstone share an unusual narrative structure, somewhat resembling an epistolary novel, in which different portions of the book have different narrators, each with a distinct narrative voice (Armadale has this to a lesser extent through the correspondence between some characters). The Moonstone, being the most popular of Collins's novels, is considered a precursor to detective fiction, such as Sherlock Holmes.

After The Moonstone, Collins's novels contained fewer thriller elements and more social commentary. The subject matter continued to be sensational but his popularity declined. Algernon Charles Swinburne commented: "What brought good Wilkie's genius nigh perdition? / Some demon whispered—'Wilkie! have a mission".