On a ship without a mission ... No one remembers where they came from or where they're going. For hundreds of years, the starship Argonos, home to generations of humans, has wandered throughout the galaxy, searching for other signs of life. Now, a steady, unidentified transmission lures them toward a nearby planet. On a planet without inhabitants ... The colony has vanished. But deep within the planet's steamy jungles, the exploration team find horrible evidence of its fate: a cavernous chamber neatly filled with rows of skeletons, each one hanging on its own hook. On a collision course with the unknown ... Once more, a signal lures the crew of the Argonos. Haunted by what they have seen, they have no choice but to follow - deep into space, where an alien mystery waits.