Most of what is known about the Roby Murders is just that reported in the papers, or is hearsay (and the statement of Doctor Lionel Trollope). Over the campaign the investigators were about to confirm the following:

• On October 14th 1926, Herbert Roby and his adult daughter Georgina were murdered at their home in Curzon St, Mayfair.
• Mr Roby, a retired diplomat, was killed by a deep wound to the upper chest and completely exsanguinated, though almost no trace of his blood was found at the scene.
• Georgina was killed by 2 or 3 blows from a large sharp implement, such as an axe, and bled profusely.
• Mr Roby's younger son, Alexander, was arrested at the scene after claiming responsibility, but instead of being charged was committed to St Agnes Asylum, Herefordshire.

Dr. Bartlett has concluded that Roby attempted to summon creatures such as The Springer Mound Monsters in order to kill his father and that the creature or creatures got out of hand. He has no real evidence for this outlandish speculation.

After meeting Roby in Carcosa, they learnt that the deaths of his Father and sister Georgina were a terrible, painful, mistake, one that Alexander will regret to the end of his days.