Pandorica

The Pandorica was a prison hidden under Stonehenge. It was built to hold the Doctor and ensure the safety of the Alliance. Despite being described time and again as the "perfect prison" by the Eleventh Doctor, it also proved to be "easy to open" from the outside; Rory Williams, on instruction from the Doctor, opened it with the sonic screwdriver.

History
According to legend, the Pandorica was the prison of a warrior or goblin who dropped out of the sky and tore the world apart until a good wizard tricked it and locked it up.

The Pandorica was actually a prison built by the Alliance for the Doctor to stop him from inadvertently destroying all of creation in every Universe. They believed the Doctor would be responsible for the destruction of existence itself. It was used to save Amy Pond. She was locked inside it for 1894 years until revived by her younger self. Her DNA provided the Pandorica the material it needed to fully revive the nearly dead adult Amy. During this time, it was moved several times.

In 118, the Pandorica was taken back to Rome under armed guard. In 420, it was plundered by the Franks. By 1120, it was the prized possession of the Knights Templar.

In 1231, it was donated to the Vatican under Pope Gregory IX. Sometime after, it was sold by Marco Polo.

It was once put into storage in a London warehouse which was destroyed by the Blitz in 1941. It was reportedly seen being dragged to safety from the burning warehouse by the Last Centurion, and found a short distance away, unscathed.

The Pandorica was also used by the Doctor to restore the universe. Since all of the traps inside it provided the perfect barrier against the destruction of the universe, it retained several billion atoms of the original universe within, even after the destruction of the rest of creation. Operating on the same principle as cloning a body from a single cell, these atoms provided a "blueprint" for the universe when the Doctor piloted it into the exploding TARDIS which had cracked all of time and space. The atoms from the Pandorica combined with the energy of the TARDIS' explosion to restore every point in time and the universe. Doing so caused the cracks in time to close and allowed Amy to remember her family and the Doctor - all erased by the cracks - back into existence. (TV: The Big Bang)

Exterior
The Pandorica looked like an image of Pandora's Box on a book found in Amy Pond's bedroom. It was lined with a very ornate and complex set of security tumblers that glowed green when they were being unlocked, likening the Pandorica to a heavily vaulted safe. (TV: The Pandorica Opens)

Interior
The interior was a small room with a chair in it and a set of manacles built into the arm rests. When someone was placed on the chair, the exterior would close and the manacles would lock around their wrists to shackle the person to the chair, sealing them in tightly. (TV: The Pandorica Opens)

The Trap
The Alliance lured the Doctor to the Pandorica by fabricating a scene with memories taken from Amy Pond. The Nestene Consciousness animated a plastic Roman legion and planted false memories in their heads, causing them to believe they were alive and real. This resulted in Rory Williams being accidentally revived after being shot and erased from history. These plastic solders sported the same gun-hands as the mannequins Rose and the Ninth Doctor encountered. (TV: Rose)

Vincent Van Gogh had a vision, which he painted, of the TARDIS exploding. On the panel that usually displays the "Pull to open" message, he painted to date and location of the fabricated Roman legion. It is unlikely that he was in on the plan, and it is more likely that he saw that date and location but not what it really was, and, figuring it was important, included it in hi painting. It might have been, however, that he was delirious and didn't even know what he was doing at the time of the painting.

The painting is next shown in the hands of Winston Churchill, shown to him by an art historian after it had just been discovered. He then attempts to contact the Doctor, but the TARDIS forwards the call to River Song because the Doctor is unavailable. He tells River about the painting, and she breaks out of Stormcage in order to track it down.

The painting found its way into the National Gallery, under the reign of Queen Elizabeth X, from where River Song steals it, attempting to get it to the Doctor. River song then graffitied the oldest cliff face on in existence, because she knows that the Doctor will visit there eventually, and, along with her trademark greeting "Hello, sweetie," leaves the date and location from the painting. The Doctor lands at that location, and finally lands himself in the trap.

After a short and smooth meeting with the Romans, moved along with the help of hallucinogenic lipstick, Amy, River, and the Doctor head to Stonehenge looking for the Pandorica. They located it in and underground chamber, and start scanning around. The Doctor is intrigued and minorly frustrated due to his lack of knowledge about the thing inside. While scanning the objects inside, the Doctor discovers that a signal is being transmitted across space, and the entire universe has come to see what it is. The Doctor finds out later that the entire universe knew what the Pandorica was for and had not come for the thing inside but rather to ensure that the Doctor was placed inside so he didn't destroy the universe. After making the discovery that all his enemies were waiting up in the sky for whatever the Pandorica was going to do, the Doctor sends river back to collect Roman reinforcements and to retrieve the TARDIS.

River returned the Roman camp, and after a short and hostile confrontation with the commander, gathers a few volunteers and sends them up to Stonehenge to help the Doctor. She attempts to pilot the TARDIS back to Stonehenge as well, but has trouble flying it until she loses control all together. She lands at Amy's house and, upon seeing strange burn marks on the ground, goes inside to discover that the people and the Pandorica are all in a book in Amy's house. She realizes it's a trap, and warns the doctor through their communicators, but the warning comes too late. She then tries to rescue him but the TARDIS lands and she opens the door to see a solid wall. She's trapped.

While River was off gathering reinforcements, Amy and the Doctor were getting attacked by a severely damaged cyberman. The cybermen temporarily disables the Doctor, and Amy hides in a small closet like area. It seems that Amy is going to get killed, but plastic Rory Williams stabs the cybermen through the chest, killing it. Amy, who had be shot by a tranquilizer dart, collapses in his arms. Amy, when she comes to, doesn't remember Rory because he got erased from time, but because she grew up with a time rift in the wall of her bedroom, she can remember things that never were and soon recognizes him.

Unfortunately this all comes to late because at this moment the trap closes. The plastic solders are activated and plastic Rory is forced to kill Amy. The Daleks, Cybermen, Sontaran, Slitheen, Judoon, and others teleport into the Pandorica cave and the plastic solders force the doctor into the open, empty Pandorica. The trap has successfully contained the Doctor, and by attempting to save the universe, the Alliance nearly destroys it.

Known inhabitants
The Eleventh Doctor was put in the chair by the Alliance to stop him from destroying the universe. Using the sonic screwdriver given to him by a future version of the Doctor, the Auton copy of Rory Williams opened the Pandorica and released him. (TV: The Pandorica Opens)

The Doctor and the Auton duplicate of Rory put Amy in the Pandorica while she was dying. She was restored when her seven-year-old self touched the box, causing it to open. Using its restoration field, the Pandorica resurrected the older Amy after it got a DNA sample from the young Amelia. (TV: The Big Bang)

Behind the scenes

 * For the Doctor Who Experience (London/Cardiff), part of the interactive story featured a device called the "Pandorica II". The Alliance trapped the Doctor in it again and it was up to the guests to bring the TARDIS to him, so he could escape. The Doctor considered the Back Up Pandorica as cheating and complained on the fact that it wasn't even a different colour.