Briar Rose resembles the original fairytales in that it is not merely a fantasy, but also an exploration of the dark side of human nature. Yolen shows that fairytales contain elements of darkness as well as light, an "angel of death" as well as a princess, and are not so innocent as they might seem. The human potential for selfishness is represented in the characters of Shana and Sylvia. In the earlier chapter, when the three sisters visit Gemma in the nursing home, the reader is confronted with opposing characteristics between Shana and Sylvia compared to Becca. The two older sisters are self-centred and egoistical, while Becca is different with them - as it is written: Becca the youngest, smiled at them both, but she was not part of their magic circle and never had been.
In some ways, Shana and Sylvia can be seen as types of the "ugly sisters" in Cinderella although they still have a good, decent part in their personalities. They try as hard as they possibly can to forbid Becca when she was going to Poland. This shows that Shana and Sylvia still care about Becca since they know that it is dangerous to go to Poland during that particular time, as Shana said in the phone call, "Well, you"re not to go. Especially with the political situation there. It's liable to blow up any minute.".
The most powerful exploration of human evil in Briar Rose comes in Yolen's portrayal of the effects of the Holocaust, first in Becca's visit to Fort Oswego and then in her trip to Poland. At Samantha's place, Becca learns about the prejudice felt by the high school students and their parents towards the refugees in Oswego. They believed the rumours that the refugees - and there were nearly a thousand of them - were living high at the taxpayers" expense. However, after they saw that the refugee camp in Oswego was surrounded by barbed wire as if these refugees were prisoners, some of the students came every afternoon to bring some snacks.