"The heresy unfolds"
- —Book's tag-line
Flight of the Eisenstein is the fourth novel in the Horus Heresy series.
Flight of the Eisenstein follows the Eisenstein, a frigate of the Death Guard Legion commanded by Battle-Captain Nathaniel Garro of the 7th Company, one of the few commanders in the Traitor Legions who remained Loyal to the Emperor.
The novel follows the Eisenstein's escape from Isstvan III (see Galaxy in Flames above) and its voyage across the galaxy in an attempt to reach and warn the Emperor of Mankind on Terra.