Lynn and Lucy are life-long best friends, their relationship as intense as any romance. Neither has ventured far from where they grew up. Lynn, who married her first boyfriend and whose daughter is fast growing up, is delighted when the charismatic, volatile Lucy has her first baby, a boy. Lucy, however, does not react to motherhood as Lynn expects. Soon, they find their friendship tested in the most extreme circumstances.

A study of escalating hysteria at a societal level, Lynn + Lucy stars Roxanne Scrimshaw in her first ever screen appearance, alongside Nichola Burley (Love and Hate, Wuthering Heights), and this highly anticipated feature by Cannes award-winning filmmaker Fyzal Boulifa.