Marigolds.

Susannah is living a typically quiet and dusty life in the suburbs with her husband Paul, when an unexpected visit from her son, Piers, surfaces a dark secret that has been brewing since he left the nest 15 years ago. As Susannah struggles to come to terms with Piers' relationship with his new girlfriend, her typical mediocre existence is slowly stripped away to reveal an obsession that is anything but typical or secret.