It was somewhat, but not entirely.

She was so tiny would Esther even have that much of a womanly figure to have to hide? I was surprised they insinuated she had breasts with the bandages they showed her unwrapping. In fact in the original script I read there was no scene of her unwrapping bandages from her chest. I would have guessed Esther would have a very underdeveloped body.

As someone, who has worked in a mental institution, I can say that the bible is the only thing patients get in their rooms. I have also noticed that many patients, who get transferred or released, take the bible with them. Being locked away in a tiny room for weeks/months can be very emotionally challenging, so the book sort of becomes their only friend for that period of time, and when they get out, they want to keep it as a reminder of - or a link to - the past, I guess. This must've been the case with Leena. Plus, it did serve a major purpose in the movie i.e. if it wasn't for the bible, Kate would've never found out about the Saarne Institute and Esther's (Leena's) past.

Russian alphabet.

Cyrillic? What does that mean.

Oh wow.

Russian school kids are always well-dressed. They don't go to school looking like slobs, like they do here in the States They also conduct themselves well. That's part of the culture.
And.. the "bible" is actually a PRAYER BOOK .. you could see the Cyrillic writing when it is opened.

to hide her physical development. Unfortunately the "Bo Peep" look is inevitable. HOWEVER, that look is not that uncommon in rural Russia.

Someone may have made the Bible a gift.

Not a psychopath. The Bible was a tool to hide and store her photos, just like the dresses hid her figure.

You get a glimpse of Bible's significance in the movie at the end credits, where we're given a few snaps of her real personality. Leena being a psychopath focuses on out-of-context Biblical phrases. As in the movie the phrase is "Suffer the little children to come unto me.
The only thing I didn't get was her dressing sense. Would have modern attire made her look less childish?

She got the Bible from the Saarne Institute and uses it for two reasons: One, to keep the photos of her male victims in, sort of like a 'trophy', and two, to make her look more "innocent." The praying and stuff was fake, just to keep up her 'Esther' image. Also without the Bible, Kate would've never found out about the Saarne Institute. It's not useless, it's clearly a plot device and a part of Leena/Esther's past.

This is exactly what I was thinking and it's kind of disappointing.
Just for the "look at her she has an old black book, oh it's a Bible, oh she's praying, what for? How mysterious!"
This is the only detail in the movie that is really useless. So I'm just waiting for someone to prove me wrong

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