Nikolai Rogozhin:  Mr. Holmes , what you have seen tonight is last , and positively final performance of Madame Petrova . She is retiring .
Holmes: What a shame .
Nikolai Rogozhin: She 's been dancing since she was three years old , and after all , she is now thirty - eight .
Holmes: I must say , she does n't * look * thirty - eight .
Nikolai Rogozhin: That is because she is _ forty - nine _ .