For all of her twenty-two years, Amy Dorrit has lived in Marshalsea prison, trapped there with her family because of her father's debts. Her only escape is to work as a seamstress for the kind Mrs Clennam. When Mrs Clennam's son Arthur returns to England after many years abroad, he takes a kind-hearted interest in poor little Amy. But when it is unexpectedly discovered that her father is heir to a fortune, some shocking truths emerge and Amy's life changes for ever.