Carolina Garcia-Ramirez is a rising star in national politics, taking on the establishment with her progressive agenda - and receiving numerous death threats in the process. Boston PI Spenser is hired for security - and it doesn't take long for him to cross paths with an extremist group called the Minutemen, led by Bishop Graves - a white supremacist social media star, who denies he's behind the attacks. As the threats become a deadly plot, it's up to Spenser to ensure the congresswoman is safe. This is Spenser doing what he does best, living by a personal code and moral compass that can't ever be broken.