"The Pandorica Opens" is the twelfth episode of the fifth series of British science fiction television programme Doctor Who, first broadcast on 19 June 2010 on BBC One.

In the episode, the time-travelling archaeologist River Song (Alex Kingston) summons alien time traveller the Doctor (Matt Smith) and his companion Amy Pond (Karen Gillan) to Roman Britain in 102 AD, where underneath Stonehenge lies a fabled prison called the Pandorica that legend tells holds the most fearsome being in the whole universe.

Amy's fiancé, Rory (Arthur Darvill), who had previously been erased from existence from one of the cracks in the universe, makes a return, though he is revealed to be an Auton duplicate outfitted with his consciousness.

The "Underhenge" set was the largest built on Upper Boat Studios and Haynes helped get the actors into the mood by playing music from the Indiana Jones franchise.

River shows the Doctor a Vincent van Gogh painting she recovered titled The Pandorica Opens, which depicts the TARDIS exploding.

The Doctor realises the Pandorica, a fabled prison for the universe's deadliest being, must be stored in a memorable location near the coordinates: Stonehenge.

While examining the Pandorica, Amy confronts the Doctor about an engagement ring she had previously found in the pocket of his jacket and feels a strong emotional attachment to.

Realising that River is at the onset of the time energy explosion that caused the cracks in the universe, the Doctor warns her to leave immediately, but she finds herself again trapped in the TARDIS as the central control console begins to go critical.

Back at Stonehenge, the Doctor discovers that the volunteer legionaries, including Rory, are Autons, and he is quickly captured as his other orbiting foes materialise around him.

Moffat chose Stonehenge as the primary location for the episode because the monument was large and important enough to be suitable for the fall of someone as powerful as the Doctor.

Haynes wanted the Doctor's speech to be his "big, pop-star moment" and to look as if he was addressing a large site such as Wembley Stadium.

[9] The script referred to it as similar to a temple found in Indiana Jones, and Haynes actually played music from Raiders of the Lost Ark composed by John Williams to help the actors slow down as they explored the set.

[8] At the episode's conclusion an alliance of many of the Doctor's enemies appear, including the Daleks, Cybermen, Sontarans, Judoon, Autons, Sycorax, Hoix, Silurians, and Roboforms.

As the Cyberman had been guarding the Pandorica for a long time, Haynes wanted to make it look "rusted, creaky, and old" and compared its behavior to Frankenstein.

A simple solution was devised to cover his arm with a green sleeve made of the same material as a greenscreen, and the final sequence is a combination of both shots.

[3] Gavin Fuller, writing for The Daily Telegraph, praised it for bringing an "epic, cinematic tale to stick in the memory" that the series had "arguably lacked", though he thought the assembly of the Alliance was "rather fanboyish on Moffat's part".

[20] Patrick Mulkern of Radio Times called it "perhaps the most epic, salivating Doctor Who ever" and praised the four leads and Moffat for "packing in surprises and slotting together the season puzzle with a dazzling plot, urgent pace and terrific dialogue".

[10] IGN's Matt Wales rated the episode 9 out of 10, saying it "managed to pack in an absurd number of standout moments" and was "beautifully delivered, if not quite as satisfying as other two-part openers thanks to its wilful evasiveness".

[21] SFX magazine's Richard Edwards awarded the episode five out of five stars, praising the "delicious twist", "great character stuff", and "touching scenes" between Amy and Rory.

[24] The Mill, Doctor Who's computer-generated effects team, won a Royal Television Society Craft and Design Award for its work on the episode.