Lamb's Blood is a novel set in Washington, D.C., Boston, and Nicaragua, 1978, during the Sandinista Revolution. American journalist Mark Marino lives with the knowledge that he allowed officials to lie to him when he was a war correspondent in Vietnam. He feels in some way responsible for the millions who died during that conflict, one of whom was his own brother. A decade later he witnesses an assassination attempt and a murder and, recognizing an opportunity to redeem himself, he resolves to bring the killer to justice. His mission leads him first to Boston, where he is reacquainted with two colleagues, Tony Rosati, and his daughter, Rina, with whom he falls in love. They discover a link between the killer, Carlos Tortue, a Vietnam veteran and former Green Beret of mixed Haitian and Nicaraguan heritage, and a Boston-based manufacturer of human blood products. Tortue kills again during an attempt on Tony Rosati's life and then escapes to Nicaragua with Marino in pursuit. Marino is no stranger to Nicaragua, having covered the Managua earthquake in December of 1972, and he immediately tries to find two men he met at that time: Jose Velasquez, a fellow journalist, and Padre Las Casas, a Roman Catholic barrio priest. Both are sympathetic to the Sandinista revolutionaries. Rina Rosati joins Marino in Managua and Las Casas arranges for them to meet with a rebel commander who allows them to accompany him and his comrades on a raid. The target is a clinic that trades in peasant blood for export, and Carlos Tortue is involved in the operation."