This volume is an account—and a symptom—of what one of the contributors calls "Cardenio fever," a malady of long standing that has had a notable recent outbreak following the appearance of Brean Hammond's edition of Lewis Theobald's play Double Falsehood in the Arden Shakespeare series (2010). A play called Cardenno or Cardenna was performed at the English court in 1613; Humphrey Moseley registered ownership of a manuscript play called The History of Cardenio "by Mr Fletcher. & Shakespeare" in 1653; Theobald declared repeatedly that his play, performed in 1727 and published in 1728, was based on a Shakespeare manuscript inherited from a Restoration theater; and the plot of Double Falsehood does indeed follow the narrative strand in Don Quix...