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 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.

• Lydia Wilson
• Joel Fry
• Joanna Scanlan
• Brendan Coyle
• Claire Rushbrook
• Tara Fitzgerald
• Clare Calbraith
• Sian Reese-Williams