Cardenio tells his story to Don Quixote, Sancho Panza, and the goatherd.
Engraving by Gustave Doré

Cardenio

"What are you, Sir?"

"A wretch, that's almost lost to his own knowledge,
Struck through with injuries-"

From Double Falshood

In 1653 almost four decades after Shakespeare's death and during the period when the Puritans had closed all the theaters in London Cardenio was entered into the Stationer's Register (an early English form of copyright) as the work of Shakespeare and his protégé, John Fletcher.

The registered work was presumably the play called 'Cardenno' which the King's Men performed at court in the winter of 1612-13. Earlier that year, the first English translation of Cervantes's Don Quixote hit the London bookstalls and quickly became the talk of the town. Since one of Quixote's main subplots concerns a mad knight named Cardenio, it's assumed that Shakespeare borrowed (or stole) Cervantes's plot for his play.

In 1727, at London's Drury Lane Theatre, Lewis Theobald staged a play he called Double Falshood, Or, The Distress'd Lovers advertised as "written originally by W. Shakespeare, and now revised and adapted to the stage by Mr. Theobald."

Furthermore, Theobald claimed that he owned no fewer than three manuscripts of the original play, one of them given to him by "A Noble Person." Shakespeare, said Theobald, gave this copy as a present "to a Natural Daughter of his, for whose Sake he wrote it, in the Time of his Retirement from the Stage."

Double Falshood (which survives as Theobald printed it in 1728) is frankly a mess but it is a retelling of Don Quixote's Cardenio tale, and it does have passages of fine poetry that sound authentically Jacobean. Most scholars now accept Double Falshood as a bowdlerization of Shakespeare's Cardenio.

Rumors have been floating about for several years that the Royal Shakespeare Company has a production of Double Falsehood in the works. Meanwhile, Shakespearean scholar Stephen Greenblatt teamed with playwright Charles Mee to write a new comedy loosely based on Shakespeare's lost original, and going by the same name. The American Repertory Theatre premiered the new Cardenio in May, 2008.

Note: In Don Quixote, the Cardenio tale begins when Don Quixote and Sancho find a dead mule in the Sierra Morena. In the Shelton translation, you'll find it in Book 3, chapter 9. In the modern translation published by Penguin Classics, you'll find it in Part I, chapter 23, p. 188.