The European best-seller - now finally presented in English! In the midst of a latent civil war between the core planets and outlying planetary settlements, an immense wall has cut our solar system in two. The black wall absorbs all light and matter, and it's up to a band of soldiers facing courts martial to investigate the phenomenon. They're the men and women of the Purgatory Squadron. For which crimes are they here? And can they work together long enough to stay alive once they enter... The Wall?