Greg Pak 
Firefly #14 [PDF ebook] 

Mal matches wits with a serial killer! The newly minted Sheriff Mal (don’t call him that, though) and Boss Moon are given their first big case as local law enforcement-to hunt down and arrest a serial killer haunting their new town! As Mal and Moon dig deeper into the mystery behind the suspicious murders, a surprising new benefactor strolls in, offering new technology and new beginnings for the townspeople…all courtesy of the Blue Sun corporation.