The play begins in Venice, where Iago, resentful of Othello for promoting Cassio over him, plots to ruin Othello. He manipulates Roderigo, who loves Desdemona, to help expose her secret marriage to Othello. The Duke of Venice learns of an impending Turkish attack on Cyprus and sends Othello to defend the island, with Desdemona accompanying him. Meanwhile, Iago begins sowing seeds of discord, exploiting others' weaknesses. In Cyprus, the threat of the Turkish fleet is neutralized by a storm, leaving the characters to focus on personal conflicts. Iago sets his plan in motion by convincing Roderigo to provoke Cassio, causing Cassio to lose his position. Iago advises Cassio to appeal to Desdemona, knowing this will make Othello suspicious and jealous.

Dramatis Personæ
ACT I
Scene I. Venice. A street
Scene II. Venice. Another street
Scene III. Venice. A council chamber
ACT II
Scene I. A seaport in Cyprus. A Platform
Scene II. A street
Scene III. A Hall in the Castle