一场警察与特务的较量，却展开满是烟火与温情的百姓人生。 新中国成立之初，派出所所长肖大力（雷佳音 饰）凭直觉锁定潜伏在土唐刀胡同15号院的特务“5182”冯静波（胡歌 饰）。为追查真相，肖大力索性搬进院落，昔日追查者与目标成了朝夕相处的邻居。 两人的交集，牵动着两个家庭、两代人的命运，岁月起落间满是波折与变故。当阅尽半生风雨，这对相伴相斗一辈子的冤家，早已不再是单纯的宿敌。 影片根据张策的小说《无悔追踪》改编。
Based on a best-selling book by New York Times national security correspondent David E. Sanger, The Perfect Weapon explores the rise of cyber conflict as the primary way nations now compete with and sabotage one another. Directed by Emmy-winning filmmaker John Maggio (Panic: The Untold Story of the 2008 Financial Crisis) and featuring interviews with top military, intelligence, and political officials on the frontlines of cyberterrorism, the documentary brings to light the combatants and innocent victims caught in the crosshairs of a hidden war that has been going on for decades — a war that America started, but has no idea how to finish. Traveling from the deserts of Iran and Las Vegas to the back alleys of Beijing and Moscow, the film chronicles America's pursuit of enemies who have plotted against its institutions, its economy, and its democracy. A never-before-seen look inside the secret world of spies, hackers, and scammers in the lead-up to the 2020 U.S. elections, for which fear of cyberattacks has mounted to an all-time high, The Perfect Weapon is a timely reflection on the ultimate price — and potential "victors" — of this high-stakes conflict.
