'Bones' Season 12 Spoilers: Final Season Gets Midseason Premiere; Plus Eric Millegan To Return

Although it seemed unlikely, Fox renewed the long-running forensic procedural series "Bones" for a 12th season, which will serve as the series final season. Season 12 will only consist of 12 episodes, but fans will not be seeing any of those episodes until 2017.

Fox has bumped "Bones" from its fall 2016 schedule to make room for its new drama "Pitch." "Pitch" will occupy the 9 p.m. timeslot on Thursdays that had previously been reserved for "Bones." Moving the new series to this timeslot will ultimately push "Bones" to a winter 2017 debut.

Meanwhile, "Bones" executive producer Michael Peterson has revealed the series will enter a "darker territory" at the end of its 11th season moving into its 12th season.

In an interview with TV Guide, Peterson said that the hunt for a new serial killer will be nothing the heroes have ever faced before and will take them to darker places. The executive producer went on to say this new killer has a fascination with mother figures, which spells trouble for one of the members of team Bones.

"It's going to have a profound effect. It is different than other [cases]. It really is going to psychologically mess with a lot of the characters," Peterson said. "The next episode where he is featured is called 'The Nightmare Within the Nightmare.' This is a person that can really haunt your subconscious."

"The Nightmare within the Nightmare" is slated as the "Bones" season 11 finale on July 21, but Peterson said that the production team have plans for this new killer to continue into the series' farewell season. "We'll probably look at them one more time in this season and one more time next season," he said. "If we're having fun we might go a little longer, but you can expect one more this season and one more [in Season 12]."

Furthermore, Peterson revealed that the ending of "Bones" will see the return of a familiar face. Talking with TVLine the executive producer said that Eric Millegan's character, Zack Addy will make a return in Season 12.

"I will say this: I know what the fans want, and as much of a roller coaster ride as we may put them through, we want to deliver," Peterson said. "I watched the show before I was ever writing on the show, and I think what Eric [Millegan] brought to that character was fantastic. I'll make a promise to try really hard to make it happen."