Mary is a beautiful modest girl and most skilful good hand in a fashionable atelier. She worked without a tiredness, not expecting no changes from life. Once on one of streets of London she was hailed by a young man in an expensive suit, a girl was frightened and dashed to hurry. However lord Мэттисон however found Mary declared that she Cora, his fiancee disappearing seven years back. A girl insisted on that she just seamstress Mary, but does not remember, from where she and as appeared in London. Мэттисон, loving dearly the fiancee, decided by all means to unriddle the secret of Mary. But for this purpose they must go back into the lock of Кингсмид.