Sneakoscope

• Type: Dark Detector, Magical Device
• Owners: Harry Potter, Ron Weasley, Bill Weasley, Alastor "Mad-Eye" Moody (used by Barty Crouch Jr.)
• Maker: Unknown

A Sneakoscope is a type of Dark Detector designed to alert its owner to the presence of deceit or untrustworthiness. The most common form, the pocket Sneakoscope, is described as a tiny glass spinning top. When it detects something untrustworthy, it lights up, spins, and emits a loud whistling noise. A much larger and more complex version was owned by Alastor Moody. It consisted of several interlinked, spindly-legged glass instruments that would whir and vibrate on a surface when detecting deception.

The primary function of a Sneakoscope is to detect untrustworthy actions or individuals in its vicinity. It serves as an early-warning system against hidden enemies, concealed Dark Magic, or general deceit. When activated, it spins, whistles, and lights up, with the intensity of the warning presumably corresponding to the level of the threat. However, the device is not always straightforward to interpret. It can be set off by minor transgressions or harmless secrets, making it seem unreliable to the uninformed. For example, Ron Weasley's Sneakoscope was dismissed as faulty when it went off during a meal on the Hogwarts Express, an event Hermione Granger attributed to Fred and George Weasley putting beetles in a fellow student's soup. In reality, it was detecting Scabbers the rat, who was secretly the Animagus Peter Pettigrew. Similarly, the large Sneakoscope in Barty Crouch Jr.'s office (while he was disguised as Alastor Moody) was constantly whistling. He claimed this was due to students telling fibs about their homework, a plausible explanation that disguised the fact that the device was constantly reacting to his own deception as a Death Eater impersonating an Auror.

• Bill Weasley owned a Sneakoscope, which he used in his work as a Curse-Breaker for Gringotts in Egypt. His parents, Arthur and Molly Weasley, sent a pocket version to Ron Weasley from Egypt in the summer of 1993.
• For his thirteenth birthday, Ron Weasley gave Harry Potter a pocket Sneakoscope. This device frequently activated throughout the school year, particularly in the presence of Scabbers, foreshadowing the rat's true identity. Harry's Sneakoscope was ultimately smashed when the Whomping Willow struck his trunk at the end of the school year.
• During the 1994-1995 school year, Barty Crouch Jr., disguised as Professor Alastor Moody, kept a large, powerful Sneakoscope in his Defence Against the Dark Arts office. This device, along with a Foe-Glass and Secrecy Sensor, served as a constant source of dramatic irony, as it was always active due to his own presence.
• In the summer of 1997, while cleaning out his school trunk, Harry Potter found his old, broken Sneakoscope and chose to keep it for sentimental value.
• For his seventeenth birthday, Hermione Granger gifted Harry Potter a new Sneakoscope. This new device proved useful during their hunt for Lord Voldemort's Horcruxes, as they used it as one of their security measures to detect approaching danger while camping in the wilderness.

The Sneakoscope serves multiple narrative functions throughout the series. In Harry Potter and the Prisoner of Azkaban, it acts as a crucial tool for foreshadowing, providing the first tangible clue that Scabbers is not what he seems. Its warnings, though dismissed by the characters, hint at the hidden dangers and betrayals that define the book's plot. In Harry Potter and the Goblet of Fire, the Sneakoscope in Moody's office is a device of dramatic irony. The reader, on subsequent readings, understands that the constant whistling is not due to trivial student lies but to the massive deception being perpetrated by Barty Crouch Jr.. In Harry Potter and the Deathly Hallows, the object represents both nostalgia and preparedness. Harry's decision to keep his broken Sneakoscope signifies his attachment to his past and his friends. The new one given to him by Hermione Granger is a practical tool in their war against Voldemort, symbolizing their maturity and reliance on every available magical advantage.

• The Sneakoscope appears in the film adaptation of *Harry Potter and the Prisoner of Azkaban*, where it is shown spinning and whistling on Harry's bedside table in the Leaky Cauldron.
• The device also appears in various video games, such as *LEGO Harry Potter*, where it functions as a detector for hidden items or secrets. (video game)