Currently, although there is no concrete evidence to prove that the Genius Club is definitely the murderer of Big Face Cat's father and Xu Yun.
But based on the known intelligence, it has the greatest suspicion and is most likely the Black Hand behind the scenes.
After all...
The Genius Club is a known organization that has spanned 600 years; if it has remained true to its original mission for 600 years, and used the same methods to cause the deaths of Big Face Cat's father and Xu Yun, it would be logically reasonable.
So, Lin Xian decided to play it safe—
[First assume the Genius Club is the Black Hand behind all this, and build the reasoning and investigation on this basis.]
"If the Genius Club indeed are just caught in the crossfire, innocent, contradictions will surely be unearthed during the investigation, and they will naturally be exonerated,"