Item from Dune by Frank Herbert
A tiny suspensor-guided assassination device — a floating needle of death controlled remotely by an operator, designed to slip through defenses and deliver a lethal poison strike.
The hunter-seeker turns every room into a potential death trap. It requires a human operator nearby — someone watching through a relay, guiding the device with a control console. The needle is coated in meta-cyanide or a similarly lethal toxin; a single scratch is fatal. Defense against a hunter-seeker requires absolute stillness. The device tracks movement — if you freeze, it loses you and searches by pattern. The operator can override and guide it manually, but that requires visual contact with the target. The countermove is to grab it from the air — seize it behind the needle before it can strike — which requires reflexes that only the highly trained possess. Paul survived a hunter-seeker in his Arrakeen bedroom on the first night after the Atreides arrived, catching it bare-handed. The incident confirmed that the Harkonnen had agents inside the palace and that Arrakis would be a battlefield, not a fief.
Barely five centimeters long. A thin metal body suspended by a miniature Holtzman field generator, with a poison-tipped needle at one end and a sensor array at the other. It floats at eye level, moving with eerie precision. Nearly silent — the faintest hum of the suspensor field. Difficult to spot in dim lighting or cluttered rooms; it moves like a malicious insect.
Also known as: seeker, hunter-seeker device, assassination probe