"Two hours before the auction began and guarded by three Legendary Rank masters?" Catherine chuckled sadly and shook her head, "You really are unlucky. Go on with the key points."
"After the gem was lost, we searched for three days," John continued, "We almost turned every suspicious place upside down secretly, but found no clues. Considering the bizarre disappearance of the gem, we suspected that it was the work of an Upper Rank thief from the Thieves' Guild, so we alerted the city guards, asking them to negotiate with the Thieves' Guild. However, traditionally, we needed concrete evidence to initiate negotiations. But the problem is that we had no evidence proving the involvement of the Thieves' Guild. Hence, they could not negotiate."
"Hmm, that's a protocol of the Thieves' Guild," Catherine nodded thoughtfully, "But why come to us? We have no evidence either and after so many days, even if there was any evidence, it probably couldn't be found now."