The prelude to this scandal came about over the Thorian belief in the Divine Avatar (a resurrection of the Emperor's soul inside a new vessel). Some Thorians believed that this might never come about naturally but instead had to be brought about through artificial means. One of those who so believed was Inquisitor Dahwrin who, in the latter years of the 41st Millennium, had gained a reputation for being an expert in such matters. He had examined, in-depth, all documentation regarding the Primarchs and the Space Marines.
However, few were aware of these studies, which were conducted during his time in the Ordo Sicarius. His time there led to him studying the shapeshifters of the Callidus Temple and whilst he did his usual duties of guarding their misuse, he began to be intrigued by the properties of the temple's shape-altering drug known as Polymorphine. In time, he discovered an isolated Callidus training outpost on the second moon of Osirian, despite the fact that few knew the locations of the hidden Assassin temples.
During his expedition to the outpost, he took with him Magos Biologis Hexun Lurd of the Adeptus Mechanicus, who was to be part of a secret experiment overseen by Dahwrin. After reaching the facility, Dahwrin declared an Inquisitorial quarantine which cut off the temple from outside interference, allowing Magos Lurd to begin experiments on polymorphine whilst using the trainees as test subjects. The aim of the project was to create a variant of the drug later known as hyperpolymorphine and use it as a means of creating a robust vessel for the Emperor's resurrection. As part of the process, the experimental drug was tested on psychically suitable subjects with a number of trials and errors leading to horrors formed by over-stimulation of hyperpolymorphine. The lucky test subjects died from the changes wracked on their bodies. After several months and nearly two dozen test subjects, one of the test subjects managed to survive a particular hybrid variant of polymorphine.
Unknown to Dahwring, Magos Lurd had his own plans for the drug and had no intention of handing over the results of his study to the Inquisition. This led to him summoning a loyal armed force of Mechanicus soldiers, which broke through the quarantine and attempted to remove the successful subject, Asaid Virenus, in order to bring her to the nearest Forgeworld for closer examination by the Techpriests. As was to be expected, Inquisitor Dahwrin struck back and fighting broke out between the two factions within the temple. This led to a three-way battle when the Master Callidus attacked both sides after she became disturbed by the Inquisitor's practices and further alarmed at the Adeptus Mechanicus learning the location of her temple. In the resultant chaos, Virenus escaped all three factions through the use of her polymorphine abilities, and remains unaccounted for.
In the aftermath of the incident, Lord Inquisitor Antigonus Balorodin led an investigation which saw Dahwrin savagely censured for his actions and led to Magos Lurd being executed for his traitorous behaviour. Inquisitor Lord Antigonus later led a search that is hunting for the fugitive assassin Virenus.