It took years of back-and-forth with CBS, but showrunner Erica Messer finally got what she wanted on Criminal Minds Season 9: a long-running storyline based around a single villain.

Referring to the unsub whose crimes viewers have witnessed twice so far, Messer told TV Guide of her discussions with the network:

"I think they were just more willing this time. Whereas before, other shows were based on that premise on the network. The Mentalist is based on somebody haunting that guy who killed his family. I think they didn't want us to compete with other shows on the network. But this year, when we pitched this idea and said, 'We'd really like to do this guy who's taunting the team,' they were like, 'We'll take it!'"

What else can Messer tell us about this mysterious individual?

He will keep "leaving bodies in his wake," teases the producer, promising that the unsub's identity will be revealed on Episode 16, though that doesn't mean an arrest or a death is imminent.

"He will likely be our ultimate case later in the year, if not the finale," Messer tells the magazine. "We've got it mapped out and things can always change because they haven't all shot, but for the most part, we know what we want this guy to end up as."

AS many have surmised from those dark room scenes of him developing shots, this Big Bad has a connection with one or more members of the BAU.

"You'll learn the connection later on. When you find out, that will be the reward at the end of the season... But we don't want the repercussions to be too much. We want to live with these characters for a long, long time and we don't want anything so bad that they can't bounce back from it."

Visit TV Guide now for a lot more from Messer and sound off: What do you think of this storyline so far?

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.