Descent of Angels by Mitchel Scanlon ,

The next instalment in the ground-breaking Horus Heresy series by Mitchell Scanlon, telling the tale of the civil war that nearly tore the human Imperium apart, ten thousand years ago. The novel explores the dark and mysterious history of the Dark Angels Legion and their Primarch Lion El’Jonson.

When the Imperial fleet rediscovers the planet Caliban, the Emperor is reunited with his missing son the Primarch Lion El’Jonson. As Dark Angels old and new join the Great Crusade, a chain of events is set in motion that will change Caliban, its people, and the Legion forever.