Their match was meant to serve the Empire. Instead, it may destroy it. Sabine Almarien has survived on cleverness and careful obscurity. But when a mark appears on her skin-one said to bind her to a magically perfect match-the Empire forces her into the Season: a cruel marriage mart where blood vows determine magical power. Worse, her supposedly perfect match is Lord Death himself. Azrian Vaelros-the Emperor's ruthless enforcer-has buried one wife already. He has no interest in another blood vow, least of all with a maddening woman who despises everything he represents. But the Emperor gives him no choice. To survive the Season, Sabine and Azrian strike a careful bargain: fake a courtship to satisfy imperial scrutiny, while quietly searching for a way out of their arranged marriage. But when other marked couples turn up dead, the two of them are drawn into a shared investigation that binds them closer than either intended. Each truth pulls them deeper into each other's orbit... and into a conspiracy at the heart of the Empire itself. As their blood vow approaches, they'll have to choose: become the perfect weapon the Empire demands, or forge something far more dangerous. Bridgerton doused in magic and murder mystery, To Break a Vow is perfect for fans of tension-filled, slow-burning enemies-to-lovers romantasy. It will appeal to readers who loved The Crimson Moth duology by Kristen Ciccarelli, Belladonna by Adalyn Grace, and Throne of the Fallen by Kerri Maniscalco.