In a quiet Portland apartment building, reclusive Leo Brunner's meticulously silent life is shattered when a man falls to his death from the balcony above. Detective Garrity sees Leo's unnerving calm as a suspicious "silent alibi." As Leo is drawn into the investigation, he uncovers a web of blackmail, noise complaints, and hidden desperation among his neighbors. To clear his own name and protect an innocent young man being framed, Leo must abandon his cherished silence, forge uneasy alliances, and expose a killer who weaponized the building's quiet secrets.