From TARDIS Index File, the free Doctor Who reference.

Gray alien
Appearance / Type:	Humanoid
Also known as:	Roswell alien
Appearances:	DW: Dreamland
Mentioned in:	SJA: Prisoner of the Judoon (indirect reference)
Notable Individuals:	Seruba Velak Rivesh Mantilax

See also the Tzun and the Nedenah, other species who apparently crashed at Roswell.

The Gray Aliens were a species at war with the Viperox during the 1950s.

Biology

The Gray aliens were short humanoids with blue-grey skin and large heads. They had large eyes, which had milky star-like matter inside them instead of pupils. (DW: Dreamland)

Technology

The Gray Aliens were thousands of years ahead of Humanity during the 1950s. They had vaguely saucer-like spacecrafts. They were a burnished red colour, with gill-like slits down the side. They were controlled by touch-activated panels. (DW: Dreamland, SJA: Prisoner of the Judoon)

The Gray aliens had glowing spheres that could heal damage. Rivesh Mantilax also created a bioweapon that was locked to the DNA of the Viperox, allowing the weapon to destroy all the Viperox in existence. It was disguised as a ionic fusion bar and could only be activated by his DNA. (DW: Dreamland)

History

In the 1940s, the Gray aliens were on the brink of war with the Viperox. They sent an ambassador, Seruba Velak, to broker a treaty with the Viperox in 1947, but she was shot down by pirates and crashed on Earth. She was kidnapped by the United States of America military and taken to the Dreamland base. There, her ship was dismantled and reconstructed, though the Humans were unable to fix it properly. Without her, the war began and the Gray aliens began to lose. In order to try to combat them, Rivesh Mantilax created a weapon that could destroy all the Viperox.

In 1948, Rivesh came to Earth to look for Seruba. He was being followed by the Viperox and was also shot down by the military, though Rivesh was saved by Night Eagle's tribe. He was adopted by them and protected by the androids sent to find him. When the Doctor was brought in to meet him, he was followed by General Stark and his soldiers, allowing them to be captured. Though Rivesh was nearly reunited with Seruba, Rivesh was injured by the Viperox Azlok, meaning the bioweapon couldn't be activated. The Doctor and Seruba were forced to go into the Area 51 Vaults, where there was the healing device from her ship. They were able to find it and bring it back, healing Rivesh and allowing him to activate the weapon, which the Doctor modified to drive off the Viperox. Following this, Seruba and Rivesh left Earth. (DW: Dreamland)

The designs for Seruba's ship were kept in the vaults. Androvax used Mr Smith to steal these schematics and commanded the Nanoforms to recreate the ship. When Androvax was caught, Captain Tybo confiscate the ship and flew it off planet. (SJA: Prisoner of the Judoon)

For the last half of the 20th century, images of Gray aliens became almost synonymous with humans claiming contact with aliens, to the point where a popular film of the 1970s, Close Encounters of the Third Kind, loosely based its aliens on accounts of the Grays. The TV series The X-Files also adapted an image of the Grays as an iconic symbol. Whether this means other Grays travelled to Earth, or this referred to the other race, Nedenah, that crashed at Roswell, or that these images all stem from the visit of the two Grays encountered by the Doctor, remains a mystery. (Contemporary accounts)

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Gray alien