Stella Crangle is introduced as a pregnant inmate in Series Three, Episode Three. She is portrayed by Lacey Turner.
Stella is a war orphan. Her orphanage was repeatedly bombed during the war, and as a result Stella never learned how to read or write, a fact of which she is ashamed. After being caught stealing, Stella is imprisoned where she soon finds out that she is pregnant. Knowing that they take babies away from prison mothers, Stella quickly fabricates a story that she has a fiance away at sea, in the hope that it will let her keep her baby if the prison board thought she was respectable.
Because she is perceived as holding herself above the other women who were imprisoned mainly for prostitution, Stella becomes a target by another pregnant inmate, who constantly torments her with accusations of being a prostitute and promises that the board will take her baby away. At a few points these altercations turn physical.
When she meets Sister Julienne, Stella tells her the same story she's told everyone else, about her fiance and that he will come back for her. After being summoned to the wardeness after defending herself in fight with another woman, wherein she is told by the wardeness that it will not help her in keeping her child, Sister Julienne is compelled to help Stella find her fiance. Knowing that Stella is trying to learn to read, the sister gifts her with the book Peter Pan.
When Stella goes into labour, she gives birth to a healthy baby boy, who she names Peter. After helping Stella learn to breastfeed, she asks Sister Julienne to be her character witness at her hearing the next day, to which Sister Julienne agrees to. When the sister inquires about the baby's father, having tried to track him down in her spare time, Sister Julienne learns that Stella has been lying. Though she wants to help, Sister Julienne says she cannot lie for Stella. Stella breaks down in tears, feeling that she now has no chance of keeping her baby.
After going before the board, Sister Julienne does not show up as witness and Stella is now certain Peter will be taken from her, having been led to believe as such by the panel. However, Sister Julienne arrives late with the news that she has found Stella a work placement at a hospital. As Stella holds Peter in her cell and awaits the board decision, the wardeness and Sister Julienne arrive and tell her that the sister has found her a job and home, and that she has been deemed a fit mother.
After leaving the prison with Peter, Stella, now able to read and write, writes Sister Julienne a letter, and tells the sister that she will always be grateful to her and will never forget her.