Department of Mysteries

"...and that's Bode and Croaker...they're Unspeakables...from the Department of Mysteries, top secret, no idea what they get up to..."

- Arthur Weasley

The Department of Mysteries is a section of the Ministry of Magic that carries out confidential research. Most of its operations are carried out in total secrecy. Few wizards within the Ministry actually know what is located within this department. Those wizards who work in the Department of Mysteries are known as Unspeakables because of the confidential nature of their work.

Some of the covert research projects this department has undertaken were revealed to Dumbledore's Army, and an important battle of the Second Wizarding War took place within the department in 1996.

Location
The Department of Mysteries lies deep in the lowest level of the Ministry of Magic, on the ninth level. It is accessible via the lifts from the Ministry Atrium. From the lift, a plain corridor leads to a black door, behind which is the Entrance Chamber, which is designed to disorient any unauthorized personnel who enter it.

Divisions
The Department apparently works to uncover the secrets of death, time, thought, and love, among other things, and records prophecies whenever they are made. It includes the following known chambers:

Entrance Chamber
This circular room has a highly polished floor that looks almost like standing water and twelve handleless doors. Whenever a door closes, the walls rotate, making it impossible to determine which door is which. This is presumably a security device to keep non-employees of the Department from reaching a desired room. This chamber will respond to a verbal request for an exit by the opening of the correct door.

Thought Chamber
This chamber is long and rectangular, lit by low-hanging lamps. It contains a tank of encephalon, or brains, that swim in a green solution. These particular brains are highly aggressive and will attack and constrict anything that tries to touch them or pick them up, as was the case with Ronald Weasley. This office seems to study the concept of thought.

Space Chamber
This is a dark room full of planets floating in mid-air. Visitors may find themselves floating as well. Luna Lovegood deemed it "a very odd place" and Reducto'd the planet Pluto at a Death Eater during the Battle of the Department of Mysteries.

Death Chamber
This large, square room somewhat resembles Courtroom Ten of the Wizengamot. It is dimly lit, with stone tiers leading down to a pit in the center. In this pit is a dais, upon which stands a very old stone archway with a tattered black curtain hanging from it. This arch separates the worlds of the living and the dead. Some people, such as Harry Potter and Luna Lovegood, will hear voices through this veil; it may be the case that those who have lost loved ones will hear the voices. Sirius Black was pushed to his death by a curse of Bellatrix Lestrange's during the battle in 1996.

The Time Chamber
This long, rectangular room is filled with beautiful, dancing light that sparkles like gems. All kinds of time-related devices fill the chamber, such clocks of every description, including Time-Turners. It also contains a large crystal bell jar at its far end, from which the sparking light comes. Inside it, anything will grow increasingly younger, to its pre-life state, be re-born to grow older, and cycle through endlessly.

At the end of the room there is a door that leads into the Hall of Prophecy. There are also small offices just off the main chamber, in which Harry Potter, Hermione Granger and Neville Longbottom faced two Death Eaters during the Battle of the Department of Mysteries.

The Love Chamber A.K.A. The Ever-Locked Room
A room behind a door that remains locked at all times and which cannot be unlocked by either Alohomora or magical unlocking penknives. According to Albus Dumbledore, behind that door is the most mysterious subject of study in the Department: "A force that is at once more wonderful and more terrible than death, than human intelligence, than the forces of nature ... It is the power held within that room that you [Harry] possess in such quantities and which Voldemort has not at all." Dumbledore later confirms that he was referring to the power of Love. The Chamber contains a cauldron full of Amortentia that Unspeakables use to study the effects of love.

The Hall of Prophecy
Records of prophecies are stored in this long, cold chamber with high ceilings and towering shelves lit with blue-flame candles. These prophecies, held in glass orbs, are magically protected, so that the only people who can lift them off their stand are the Keeper of the Hall of Prophecies and the subject or subjects of the individual prophecy. Anyone else who attempts to inspect the orb with their hands will be afflicted with instant madness.

Known Prophecies
A year before Lily and James Potter were murdered by Lord Voldemort, the seer Sybill Trelawney made a prophecy involving Voldemort and a child who would come to be his destroyer. After his return, Voldemort sought to know the entire prophecy and lured Harry and other members of Dumbledore's Army to the Hall in attempt to steal and confirm the contents of the orb. Due to the incompetancy and failures of the Death Eaters, the orb was shattered in a commotion that prevented anyone from listening to the contents.

The Department of Mysteries had not fully recovered as of the September of 1996. At one point, it was mentioned that the Department's entire stock of Time-Turners was smashed during the Death Eaters' botched infiltration of the Ministry. There was also the implication that it had not managed to replace them.

Known Employees

 * Broderick Bode
 * Croaker
 * Augustus Rookwood

Trivia

 * Luna Lovegood – probably influenced by an article in The Quibbler – once stated that Minister for Magic Cornelius Fudge "uses the Department of Mysteries to develop terrible poisons, which he secretly feeds to anybody who disagrees with him" . There is no proof that this is true.
 * The name of the department may be an allusion to the Mysteries of the Ancient Greek and Roman religions, in which admission and knowledge was restricted through arcane initiation rites. The Eleusinian Mysteries were the most famous and important of these.