Bones just ended its eleventh season last night. Recently, star Eric Millegan spoke with TVGuide about his surprise return and the upcoming final season of the FOX series.

SPOILER ALERT! Millegan plays Zack Addy, who was just revealed as the kidnapper of Dr. Temperance Brennan (Emily Deschanel) in the season 11 finale.

When asked about what his character’s been up to since he left after season three, Millegan said “people will not be disappointed”:

He has done a lot. I say at the end of the episode, “We have so much to talk about.” Obviously, we don’t know what that is and the audience won’t find out until January. I start shooting on Monday and he’s been doing a lot. I wish I could say, but he’s been through a lot. He’s done a lot. It’s amazing how they’ve developed my character from the beginning of Season 1. I can tell you, you’re going to love it and people will not be disappointed.”

He added that viewers will find out everything when season 12 starts:

The last time we saw Zack in real time was 8 years ago. There’s a big hole with what’s going on with him. He respects her. He is innocent of murder. He does feel that he was the accomplice to a serial killer so he feels like he would go to jail if people found out what he did. He wants to stay at the mental hospital where he feels he would do better. He is not crazy. Sweets knew he wasn’t crazy. Now, we have to deal with the fact that two years ago Sweets was murdered so nobody knows that Zack didn’t kill anyone. In episode 1 of Season 12, everyone is going to find out exactly what Zack has been up to. It’s a big episode. You find out everything.”

Millegan also teased that Zack may not be the killer you think he is:

I can say this: when they announced that I was going to be on and they were doing this puppeteer storyline, I talked to Tamara [Taylor]. She said that when she heard that I was coming back, she and TJ [Thyne] went to Michael Peterson, who wrote the finale and [next season’s] opener, and said, “You can’t make him a killer. We’ve been through that already. You have to make him the hero.” I have my colleague going to bat for my character.”

Season 12 of Bones debuts in early 2017.

What do you think? Do you watch Bones? Were you shocked by the season 11 finale? Are you excited for the final season?