Broken Oaths
The brilliant third novel from the acclaimed author of THE COLOURS OF DEATH.
During a remote meeting, an official watches from Lisbon as his colleague, Inácio Machado, a Portuguese diplomat based in London's Portuguese embassy, dies of what looks to be a heart attack. When no one comes into the room to Inácio's aid, he tries frantically to contact the embassy to get immediate help. He tries and tries again, but no one picks up the phone and he's forced to call the British emergency services.
When local police arrive, they walk into a disturbing scene. Everyone inside the building is dead, all seemingly from the same cause.
Inspector Isabel Reis, a Gifted Inspector with Portugal's PolÍcia Judiciária has developed a reputation for closing sensitive cases involving powerful people. When the gravity of what has happened in Belgravia is revealed, she's called up to London to assist London Met's CID in the investigation.
The mystery takes another alarming turn when they realise that the embassy was harbouring an American-Portuguese military scientist who is unaccounted for.
One thing becomes clear very quickly: the deaths are murders, and Isabel faces capturing a killer more ruthless than she has ever seen before.
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Patricia Marques
In a version of Lisbon just a step sideways from our own, where telepaths are real and suspicion runs deep, Patricia Marques invites readers into mysteries that don’t just ask whodunit—they ask who do we trust when thoughts aren’t private?
Born in Portugal and raised in London, Marques grew up between worlds, a reality that quietly echoes in her fiction. Her Inspector Isabel Reis series blends crime fiction with speculative elements, creating an atmospheric hybrid where psychological tension hums beneath every page. In novels like The Colours of Death and House of Silence, she probes questions of identity, power, and prejudice—not through heavy exposition, but through tightly woven plots that unfold with quiet intensity.
Inspector Reis
Inspector Reis consists of four books and considered as a complete series. The current recommended reading order for the series is provided below.


