A woman wakes up in a trashed apartment, covered in bruises, with deep, painful scratches carved into her shoulder. In the shower, blood streams off her aching body. Still in shock, Julia (Martina Gusman) only realises hours later that two men are in the flat with her - one, her boyfriend, has been stabbed to death, the other - Ramiro, her boyfriend’s lover - is badly injured but still alive. Unable to remember what happened, she’s thrown into jail by the police, where she soon discovers that she’s pregnant.

Lion’s Den, the fifth film from Argentine director Pablo Trapero, could not be further from the exploitation films that characterised the women in prison genre in the 70s. The movie is named for the penitentiary units where women with children are housed during their incarceration. In Argentina, the children are allowed to remain inside with their mothers until the age of four, when they’re removed by the Court and either placed with a relative or in state care.

Julia finds herself in a shockingly decrepit cell. The other mothers are mostly uneducated, peasant women, in sharp contrast to Julia’s rebellious but upper-class character. Trapero captures all the gritty realism of life in prison, but the film also has the feel of a slow-burning thriller - as Julia adjusts to life on the inside, her case pits her against Ramiro (played by Rodrigo Santoro), who accuses her of being solely responsible for his lover’s death.

With her life shattered, Julia struggles with motherhood. Unable to breastfeed after her son, Tomí¡s, is born, she’s helped by her cellmate Marta, who intervenes when the baby’s cries begin to drive the other mothers and children over the edge. Older and more experienced, Marta takes Julia under her wing, eventually leading to a relationship between the two women, who manage to find some small comfort in the confines of the prison.

But the wheels of justice are grindingly and appallingly slow: Julia gives birth and raises her baby behind bars without ever going to trial. As Tomí¡s gets older and approaches the all-important age of four, Julia’s distant, beautiful and unwelcome mother (played by the singer and actress Elli Medeiros) intervenes, returning to Buenos Aires from her life in Paris to take over the role of looking after her grandson, with disturbing and dramatic consequences.

Filmed almost entirely within an existing women’s penitentiary, using real inmates and guards as extras, Lion’s Den is a deeply harrowing film. Martina Gusman, who won the FIPRESCI International Critics’ Prize for best actress, delivers a powerful performance as a determined mother who will do anything to keep her child. While the film, released so soon after Jacques Audiard’s A Prophet, may not be as polished, or as entertaining as the French thriller, it is a more brutal, realistic and morally ambiguous portrayal of life in prison.

Although the film’s ending may seem a little unconvincing, Trapero never offers the audience any easy answers. We never really discover the truth behind the murder, and are left to decide whether a mother’s love for her child is more important than an innocent child’s right to freedom and a life outside prison.

Sarah Cronin