Natalie Portman is going in — but is she ready to find what's on the other side?

Paramount debuted the chilling first trailer for "Annihilation," an adaptation of Jeff VanderMeer's novel by "Ex Machina" writer/director Alex Garland. Natalie Portman stars as a scientist who goes on an expedition with three other women into an area quarantined for abnormal activity by a mysterious creature.

She goes in to save her husband (Oscar Isaac, re-teaming with his "Ex Machina" director) and uncover just what this creature is. But it may just defy categorization. "You really have no idea what it was?" one investigator asks Portman.

Much like "Ex Machina," the tone of the trailer is unsettled and creepy. It looks fantastic, too — the quarantined area features some twisted, disturbing vistas. Jennifer Jason Leigh, Gina Rodriguez, and Tessa Thompson are also along for the haunted horror ride.

"Annihilation" opens in theaters February 23, 2018.