A pair of twins is hunted by aliens or monsters

Jason Dessen is abducted into an alternate version of his life. To get back to his true family, he embarks on a harrowing journey to save them from the most terrifying foe imaginable: himself.

Liu Xing a brilliant Chinese student, arrives at University and makes the transition into American life with the help of Joanna Silver. Xing joins a cosmology group working to create a model of the origins of the universe. He is obsessed with the study of dark matter and a theory that conflicts with the group's model. When he begins to make breakthroughs of his own, he encounters obstructions.

When a young boy vanishes, a small town uncovers a mystery involving secret experiments, terrifying supernatural forces, and one strange little girl.

Oona, a recent graduate in anthropology, has returned to her dead mother’s seaside cottage in southern England to prepare it for sale. Her arrival disturbs Mani, a wary vagrant who has been squatting on the property.

16-year-old Cassie Sullivan tries to survive in a world devastated by the waves of an alien invasion that has already decimated the population and knocked mankind back to the Stone Age.

A few years from now, Earth will have the first contact with an alien civilization. These aliens, known as Newcomers, slowly begin to be integrated into human society after years of quarantine.

Detective Matthew Sikes, a Los Angeles police officer reluctantly works with "Newcomer" alien George Francisco. Sikes also has an 'on again off again' flirtation with a female Newcomer, Cathy Frankel.

Two identical twins, who were separated at birth, go on violent killing sprees thirty-five years later on the very same day. They are soon on a deadly path that will bring them face-to-face with each other.

The massacre of the Levi family, of which only adopted twins Eva and Greta survive, pits priests Father Michel and Father Paul against the powers of evil, both convinced that the twins are diabolical.