After Delphine Rousseau refuses billionaire arms broker Tariq Vance and is assaulted in a Paris alley, a passing former Navy SEAL now training as a NASA astronaut, Joe Straightback, intervenes and stays to make the violence answerable.

Carrying copied manifests that expose Tariq’s weapons-diversion network, Delphine relocates to a protected Texas ranch under a federal task force, where Joe surfaces again because Tariq’s shell companies touch his mission’s hardware supply chain.

As the investigation braids toward a Houston port-and-smelter operation, Tariq escalates from surveillance to targeted threats against both Delphine and Joe’s launch, and the two trauma survivors—she terrified of ordinary loss, he convinced his darkness leaves widows—work the case and their attraction under mounting danger.

Tropes: protector hero, witness in protective custody, forced proximity on an isolated ranch, stalker/obsessed antagonist, wounded lethal hero with a soft spot for one woman, guarded heroine with a traumatic past, competence-as-attraction, found family, slow burn, touch-her-and-you-die, explicit negotiated intimacy with aftercare