After more than 10 years in production and 11 eventful seasons, Fox crime mystery series “Bones” is gearing up to come to an end. The Season 11 finale aired on Thursday, July 21, reintroducing Zack Addy (Eric Millegan) — a character most haven’t thought about since eight seasons ago when he last showed his face. What did the intern-turned-doctor want with Temperance “Bones” Brennan (Emily Deschanel) and Seeley Booth (David Boreanaz)? Check out our detailed breakdown of the season finale:

During “The Nightmare in the Nightmare” Brennan and Booth were on the hunt of a serial killer, aptly named The Puppeteer, who’s been killing people and turning them into marionettes. This particular case has been troubling Dr. Brennan, who blames herself for letting the killer reign for so long. The murders began while she and Booth were off the job and it took quite some time for them to dust off their detective skills and get back in the game. The Puppeteer gets a glimpse at Brennan and Booth, who were able to track down his helper but not him, and takes a particular interest in the female half of this crime-solving duo.

Brennan begins to feel as though she’s being watched — and she’s not wrong. The killer strikes again, murdering Melissa. The murder hit home with Brennan, as The Puppeteer intended it to. She and Melissa shared a lot of similar qualities. The pair looked alike — especially after the serial killer dressed her in Brennan’s old clothes. Brennan began having nightmares related to the killing and decides the best thing to do is go talk to the therapist Melissa was seeing before her death. Her husband urges her not to, hoping that just chatting with him would be enough to soothe her pain.

Booth decided that if talking it out wasn’t going to work for his wife, he’d do the next best thing and track down another Puppeteer associate. He is able to, but the person turns out to have been a mere pawn in the killer’s game. Still, it helped him to understand his wife’s uneasiness a little more. Booth realized that the associate he’s uncovered was not the only one who got played by The Puppeteer — it was his pattern. This caused Booth to question why that pattern changed when it came to Melissa’s murder. Melissa simply didn’t fit the profile — she had a history of run-ins with the law and was once fired for embezzling money. Hardly the parental figures The Puppeteer had been going for. Booth and James Aubrey (John Boyd), a junior FBI agent, began brainstorming reasons Melissa may have found herself a victim of this senseless murder. Both felt that there was no way she was a warning, despite The Puppeteer’s clear call-out to Bones. Instead, they deduced that Melissa must have gone to the killer for advice — meaning it was someone she knew and trusted in some way.

Meanwhile Bones remained vigilant in her therapy sessions, which were bringing her and Booth closer than ever to uncovering Melissa’s murderer. While Brennan continued to struggle with her nightmares, Booth decided to take action. He visited her shrink’s office and demanded that he give him the notes he’d taken during his talks with Brennan. In them, Booth learned that she’d been having nightmares about her former intern, Zack — yes, that Zack. The one that was cleared of wrongdoing in Season 4 after it was revealed that he had simply aided a cannibal killer, not killed anyone himself. The camera then flashed a look at Zack’s room in the mental institution he was taken to rather than jail — his bed was empty.

Brennan then woke up from what she thought was another sick dream, but she’s wrong. This nightmare is real and her fears about Zack turn out to have been legitimate. Zack told Brennan he was thrilled to see her again and the episode came to an end.

Fans of “Bones” will have to wait until winter to find out why Zack has taken an interest in Brennan. The show will air it’s final season in 2017.

Brennan (Emily Deschanel) and Booth (David Boreanaz) cracked an important case involving an old friend during Season 11, episode 22 of Fox’s “Bones.” Fox