The prisoner of Limnos : a fantasy novella in the world of the five gods
(Book)

Sequel to: Mira's last dance, but released after: Penric's fox.

Series numeration from goodreads.com.

Penric and Nikys receive a letter from a friend warning them that Nikys's mother has been taken hostage, and the pair set out to rescue her --,adapted from publisher description.

Penric, a Temple sorcerer and learned divine, and the widow Nikys receive a letter from a friend warning them that Niky's mother has been taken hostage by her brother's enemies, and confined in an island sanctuary. The pair must put their romance on hold and set out to the rescue. They soon find that family relationships can be as unexpectedly challenging as any rescue scheme. -- adapted from jacket and goodreads.com info