Lena appears on screen but her face is never shown. A voiceover reads her letter to Ivan but her character is not mentioned in the credits.
When Charyshev reads Lena's letter, the order of the sentences as read by the voiceover is different from the order of the sentences in the letter that can be seen on the table after he reads it.
At the beginning of the first scene at Ivan's place, a poster with Lena's name is partially seen on the left-hand wall. We can only see the surname, Charysheva.