'A party of tourists are being, shown through Edinburgh Castle when a tale told by the guide, coupled with the music of a spinet, recreates in the mind of one of them an episode of the past, in which she fancies herself to be taking part. After the due interval of dimmed lights and rippling music this episode comes on the stage. After an other similar interval the dreamer returns to the present' ('Polygon.' 'Two Local Plays,' p.15).
The fantasy story revolves around Mary Queen of Scotts and her infant son (later King James I of England). The title of the refers to the Queen's four maids-in-waiting who are all named Marie.