What if you discovered that your parent had lied to you? That almost everything they'd said about their own history, and yours, was untrue? In 1994, a toddler disappeared from a small Welsh village, never to be seen again. 23 years later, in London, the mother of rising cello star Matilda Gray (Lydia Wilson) commits suicide, without apparent reason. Among her possessions, Matilda discovers tantalising evidence, linking her mother to the Welsh girl's disappearance all those years ago, sending her grief-stricken to Wales. Determined to find out who she really is, Matilda unravels her own identity and exposes long buried secrets that a remote community are trying desperately to forget. One secret is more bizarre, terrifying and dangerous than anything she could have imagined one that has been waiting many years for Matilda to return.