在这部神探贝克：黑暗中的轨迹悬疑/犯罪片中,
Commissioner Beck and colleague-lover Lena Klingström finally booked a common holiday, but soon find neither con concentrate on it after Gunvald Larsson and the press report an apparently senseless slash-murder in the Stockholm metro system, so Lena prefers to return. Sulking Beck is made team leader of a task force, which soon includes other corps. The home of missing conductor Erik, on whose shift a murder was committed, Beck is alarmed finding elaborate network plans, and an Internet-sign for "death". Beck looses charge, having made no progress after three more murders, but disagree with terror specialists comparing the case to the religious fanatics' Tokyo poisoned gas slaughter. The tunnel system is closed and searched, Beck finds Erik hiding there, fearing his sister Annika's young video-gaming-in-real-life gang, which stages power cuts to reach a higher level by bloody killing.
