The play is very loosely based on the history of the troupe. The plot centers around Isabella Andreini's joining of the group in its early days, elevating them from poor street performers to massive success with her acting and poetry, and the revolutionary act of allowing a woman to perform onstage. Their attention earns them the patronage of the Duke of Mantua and their official adoption of the I Gelosi title. Throughout this, a romance buds between Isabella and Francesco. The play dramatizes the company's travels to France, where they perform a play satirizing the Pope that thrusts them into a scandal. They become involved in the Huguenot Rebellion on both sides, taken hostage by the Huguenots and labeled spies by the monarchy. They flee to Mantua only to be turned away for the controversy they have created. Isabella begins to go mad, and turmoil and conflict arise within the group. The play ends with Isabella dying, and the troupe being disbanded, their success lost and returning to poverty.
The play is a fictitious account of the troupe, with the plot elaborating and dramatizing facts of the company's travels.