During the Magical Dreamers concert, two stars are referenced: Diarmuid and Grania. Before, I had figured that these were made up names, but I checked Wikipedia and they stem from Irish mythology.
From Wikipedia:
Diarmuid
In Irish mythology, Diarmuid Ua Duibhne (also known as Diarmuid of the love spot) was son of Donn and a warrior of the Fianna. Aengus Og was the foster-father and protector of Diarmuid.
Diarmuid met a woman who caused a magical love spot to appear on his head; any woman that looked at his head fell in love with him.
Grainne, bride of Fionn mac Cumhail, fell in love with Diarmuid. He ran off with her and was finally killed by a giant boar on the heath of Benn Gulbain.
Grainne
In Irish mythology, Gráinne was the daughter of Cormac mac Airt.
She was promised in marriage to Fionn mac Cumhail, but fell in love with Diarmuid of the love spot when she saw Diarmuid in the wedding party. She laid a geasa upon him to run away with her. Their long flight from Fionn was aided by Aengus Og, Diarmuid's foster-father.
Eventually, Fionn pardons Diarmuid after Aengus Og intercedes on their behalf; the pair settle in Kerry and produce five children. The story of Gráinne and Diarmuid is one of a number of instances in Irish mythology of the eternal triangle of young man, young girl and ageing suitor. The situation is very similar to the tale of Naoise, Deirdre and Conchobar. The same theme also shows up in other, Celtic-influenced cultures, most notably the tale of Tristan and Iseult (with King Mark of Cornwall), and more famously, Lancelot, Guinevere, and King Arthur.
The LÉ Grainne (CM10), a ship in the Irish Naval Service (now decommissioned), was named after her.
~
Daniel, if that mythology dictionary is of any help, feel free to offer its knowledge up here.