Musgrave also wrote the libretto based on Peruvian writer Amalia Elguera's play Moray.

It focuses on events in the life of Mary, Queen of Scots, from her return to Scotland in 1561 until 1568 when she was forced to flee to England.

[2][3][4][5] A commission from Scottish Opera, Mary, Queen of Scots was given its world premiere by the company at the Edinburgh Festival on 6 September 1977.

Over the next two and a half years Scottish Opera took their production on tour to multiple UK cities and gave one performance in Germany at the Staatsoper Stuttgart in May 1978.

The US premiere was performed by Virginia Opera on 29 March 1978 in a new production directed by David Farrar and conducted by Peter Mark.

Mary's arias also appear in Musgrave's 40-minute triptych, Three Women: Queen, Mistress, Slave, a narrated assemblage of scenes for the leading female characters from Mary, Queen of Scots and Musgrave's later operas, Simon Bolivar, and Harriet, the Woman Called Moses.

The triptych had its world premiere in January 1999 at the Herbst Theatre in San Francisco with Amy Johnson singing all three heroines.

At a court ball organized by David Riccio, Mary first encounters her cousin Lord Darnley and is fascinated by him.

Determined to assume even greater power over Mary, James again earns her mistrust and ultimate estrangement, made worse when she discovers that he was behind the murder of Cardinal Beaton.

James then instigates a plot to goad Darnley into murdering Riccio by convincing him that he is the real father of Mary's child.

Mary appears in the crowd and accuses James of perfidy, including arranging Riccio's murder to discredit her.

Act 3 Exhausted and ill after the birth of her son and with her resolve to "stand alone" now weakening, Mary hears from Lord Gordon that James has raised an army and is turning the people against her.

Gordon arrives with the news that Darnley has been murdered and learns that Mary as now been hopelessly compromised by Bothwell's actions.