[2] Ingmar Bergman adapted her novel Det vänliga, värdiga (1954) in 1958, and after that he hired Isaksson to write the screenplay for the film Jungfrukällan (1960).
Several of Isaksson's novels of the 1950s are marked by religious problems, as ultimately in Havet and Dit du icke vill, where 17th century witchcraft trials in a village in Dalarna are portrayed of the bases of contemporary protocols.
In later novels she also directed analysis against erotic motifs, world problems, women's issues, and parenting.
Boken om E was adapted for the screen in 2001, directed by Bille August, and entitled A Song for Martin.
Isaksson died on 24 April 2000, before the adaptation of Boken om E. The book portrays a couple whose love, in combination with psychosis and religious blindness, causes them to go under.
The other women living in the house have a hard time understanding her toleration and her indifference to the husband's doings.
Ulla Isakssons autobiographical account of how her husband Erik Hjalmar Linder suffered from Alzheimer's disease.