[Vocabulary] "fly to the fakement"

[imchongjun]

Could you please tell me what the last sentence means in the following quote from a Victorian novel?

"Mercy, mercy! I implore you! Oh! do not devote me to so horrible a death! Do not - do not murder me!"
"Hold your noisy tongue, you fool," ejaculated Bill, brutally. "You have heard and seen too much for our safety ; we can't do otherwise."
"No, certainly not," added Dick. "You are now as fly to the fakement as any one of us."

The first speaker is an innocent boy, and the second and third speakers are ruffians. I don't understand the "You are now as fly to the fakement" part. What do "fly" and "fakement" here mean? I appreciate any comments. Thank you.

 

[Rover_KE]

Welcome back after your three-year furlough, imchongjun. :-D

Could you please tell me what the last sentence means in the following quote from a Victorian novel?

Please tell us the title and author of the novel.

 

[imchongjun]

Thank you for your warm reply.
Though I didn't post a message, I have been checking this site regularly.
The quote is from The Mysteries of London by George W. M. Reynolds (1844).

 

[probus]

"Fly to the fakement" appears to be outmoded British slang. In modern American slang it could be rendered as "in on the scam."