In the uneasy weeks after Sylvanas Windrunner abandons the Horde she once led, her former agents Nathanos Blightcaller and the loa Bwonsamdi pursue their own designs while Thrall, Baine Bloodhoof, and the Horde's remaining leaders scramble to hold their alliance together and choose who leads them next. Madeleine Roux's novel bridges the Battle for Azeroth and Shadowlands expansions, setting up the fractures the latter explores in full.
Summary by Loreful, from public sources