Kalinke and Mitchell summarise the saga thus: Presumably either a thirteenth-century translation from a lost version of the French Partenopeus de Blois, or an Icelandic reworking of a lost Norwegian translation.
Partalopi, son of King Hlöðvir of Frakkland, is transported to Miklagarð where he becomes the lover of Marmoria, a maiden king, who remains invisible to Partalopi, while he remains invisible to her courtiers.
Marmoria warns Partalopi that any attempt to see her will result in his death.
After a succession of adventures, the lovers become reconciled, marry, and rule jointly.
[1]Kalinke and Mitchell identified the following manuscripts of the saga:[1]