In British film-maker Kim Longinotto’s tough but remarkable new documentary, she focuses on the work of Brenda Myers-Powell, an early contender for saint of the year – an ex-prostitute who has overcome a life of abuse to devote her time, unpaid, to helping other women in similar situations around Chicago. Like the film, she’s calm, non-judgmental and engaging and despite her undeniable star quality (an award-worthy biopic feels like the next logical step), Longinotto doesn’t impose a conventional narrative on her story, or those of the women she helps, and gives them the chance to share their harrowing stories without any forced emotional beats. It’s grim, unfussy and deeply moving.