The fifth of ten books in The 39 Clues series, The Black Circle brings readers to a halfway point in the adventure of 14-year-old Amy Cahill and her younger brother Dan. Previous instalments have seen the clue-hunting siblings travel around the world looking for the answers to the Cahill family mystery.
Launched into their adventure by the mysterious message in their grandmother’s will, Amy and Dan have travelled around the world, often accompanied by other members of their extended family or by their au pair, Nellie.
In The Black Circle, Amy and Dan strike out alone and find themselves in Russia, discovering secrets about the disappearance of the Russian princess Anastasia and the murder of her family. Amy and Dan must decide whether to risk falling into a trap set by the scheming Lucians in order to gather more clues and possibly find out what happened to their parents on the night they died.