Young Adult Historical Fiction discussion

How are you guys liking Between Shades of Gray? What are your impressions of Lina, Andrius, Josef, Elena, all the other main characters (especially characters like Nilai or the old man, who seem sometimes bad, sometimes good)? Any opinions as to how the title connects to the plot?

*Naturally, when discussing a book's plot many minor spoilers will be revealed. However, if you are going to post about something that could be considered a major spoiler, please use spoiler tags. Since everyone is reading at a different pace, it will give other members a choice as to which spoilers they see. Thanks!