Measure for Measure, a “dark” comedy in five acts by William Shakespeare, written about 1603–04 and published in the First Folio of 1623 from a transcript of an authorial draft. The play examines the complex interplay of mercy and justice. Shakespeare adapted the story from Epitia, a tragedy by Italian dramatist Giambattista Giraldi (also called Cinthio), and especially from a two-part play by George Whetstone titled Promos and Cassandra (1578). The play opens with Vincentio, the benevolent duke of Vienna, commissioning his deputy Angelo to govern the city while he travels to Poland. In actuality, the duke remains in Vienna