Six tourists hire an extreme tour guide who takes them to the abandoned city of Pripyat, the former home to the workers of the Chernobyl nuclear reactor. During their exploration, they soon discover they are not alone.

"On a spring morning, neighbors Valentina Kaplan and Oksana Savchenko wake up to an angry red sky. A reactor at the nuclear power plant where their fathers work--Chernobyl--has exploded. Before they know it, the two girls, who've always been enemies, find themselves on a train bound for Leningrad to stay with Valentina's estranged grandmother, Rita Grigorievna. In their new lives in Leningrad, they begin to learn what it means to trust another person....