They are the only ones who did not fight in the battle of birds and beasts. They should never see the sun. Their time is night. This was the sentence passed on a flock of silver-winged bats many years ago. But the Higher Powers made a Promise that one day the ban would be lifted. During a terrible storm, the young silver wing Shade lost his flock, but in return he met a faithful companion - the bat Marina. Unfortunately, Marina was once ringed by people and the flock turned away from her. Shade is sure that the rings have something to do with the Promise, but the path to solving this mystery is too dangerous - merciless enemies wait at every turn, and friends betray and break the Law. Brave Shade knows that the risk is great, but he will not spare his life, to return the sun to your flock.