In early 20th-century China, anthropologist Alexander Saxton discovers a frozen, prehistoric creature and arranges to transport it to Europe via the Trans-Siberian Express. Fellow scientist Dr. Wells is intrigued by Saxton's secretive behavior and manages to bribe a porter to peek inside the crate. When the porter is found dead, his eyes turned white and bleeding, suspicions arise about the nature of the creature. Soon after, passengers on the train start dying mysteriously, with the telltale signs of white, bleeding eyes.

As panic spreads, Saxton and Wells investigate alongside Polish Countess Irina and spiritual advisor Father Pujardov. They uncover that the creature is an extraterrestrial being capable of transferring its consciousness into other hosts by draining their memories and knowledge through the eyes. With the creature on the loose aboard the confined train, Saxton and Wells must race against time to stop it before it annihilates everyone on board.