I'm betting the title was chosen partly because of the popularity of the series with a similar title. However, Between Shades of Gray is a young adult fiction book based on the "relocation" of tens of thousands of Lithuanians, Estonians, Latvians and Finns when the Soviets took over those countries in 1941.
Lina tells the story beginning with this line: They took me in my nightgown.
The Soviets gave Lina, her mother Elena, and her brother Jonas twenty minutes to pack whatever they wanted to carry in a suitcase. The family was herded into cattle cars with hundreds of other townspeople where they spent six weeks on their way to Siberia.
Once there, they were told to sign documents that declared them to be criminals with a sentence of 25 years at labor in the beet and potato fields. They were given only a little bread to eat. Many died of scurvy and other diseases caused by living in noxious conditions.
As Elena wouldn't sign the documents, she, Lina, and Jonas were sent clear across Asia to the northern end of the Lena River above the Arctic Circle.
This family lived through the horrors of Stalin's dictatorship. The story seems to have a better - although not completely happy - ending. Lina's story is eventually found buried in a jar in 1954. She was never able to speak about it openly due to the Soviet strictures.
While not a comfortable story, it is based on what really happened to the Baltic Coast countries during World War II. It was a different kind of Holocaust occurring at the same time as the Nazi destruction of the Jewish people.