Edwards was one of the men who met regularly with Alexander Roby in late 1925. This information came from both Delia Morrison and Vincent Tuck. The group also included Lawrence Bacon, Malcolm Quarrie and possibly a man called Coombes.

Aged about 40, neatly-dressed and sporting a beard and moustache, Edwards lived alone in short-term lodgings at 50 Berriman Road in Islington. Neither Delia, nor Tuck found out his first name. He spent his time in the library and meeting the other men, and despite driving a car did not appear to be employed.

Referred to by Alexander Roby during his monologue to Dr Bartlett, Roby said the following:

• Edwards told Roby to work only with him.
• Roby and Edwards were in some way opposed to, or in disagreement with Malcolm Quarrie.
• Roby also says “What Edwards and I are doing now harms no one.”

After the disappearance of Alexander Roby and Nurse Evans from St Agnes Asylum it was discovered that his full name is Montague Edwards and that he had been at the Asylum all along, posing as Nurse Mark Evans.

The obituary of Lawrence Bacon printed in Occult magazine refers to Edwards as the “Laird of Mullardoch” which ties him to Loch Mullardoch in Scotland.

Edwards had a reader's ticket for the British Library, for which his references were Malcolm Quarrie and Dr Schwabe, his former teacher. Schwabe remembered Edwards and was able to give a little more information about him.

As a young man Edwards attended the Slade School of Fine Arts, but showed no real desire to graduate or exhibit, despite his talent. He dropped out in 1907 and seems to have disappeared from society.

While at Slade he saw slides of the 1907 Oxford University dig at Springer Mound and seemed to show great interest in them.

As witnessed by the investigators in Carcosa, and explained by Roby, Edwards had come away from encountering Hastur on Springer Mound with an unnatural ability to regenerate from the effects of physical damage, which he had refined into a particularly bloody form of masochism. This seems to explain the large amounts of blood found at the scenes of the Asylum murders, and Lucius Harriwell's stories of the Devil being covered in cuts.

There can be no doubt that Montague Edwards was the Asylum killer.

In December 1928 Edwards took Alexander Roby to Loch Mullardoch and called Carcosa to Earth. On the 10th of December, while attempting to summon Hastur, Edwards was foiled by Roby, apparently using The Chime of Tezchaptl and his blasted corpse was hurled back to the real world, where it was discovered in Mullardoch House.

Shortly after this, the corpse changed into a hideous scaly form with boneless arms and attacked Nathaniel Browne, who was saved by Bartlett and Withers. After being pinned to the wall with a garden fork, the creature was finally killed with a rifle bullet through the brain, after which Edwards was apparently finally dead. His hideously disfigured corpse has been explained by the police as the result of being attacked with acid, probably by Roby.