Eddie McClintock's Sully will make a shocking comeback in "Bones" Season 12. That said, executive producer Michael Peterson teased what's in store for the upcoming episodes plus, the official plot description and the promo clip for episode 3 'The New Tricks in The Old Dogs' is released.

According to Buddy TV, Eddie McClintock is set to return as Dr. Temperance Brennan's (Emily Deschanel) ex-boyfriend FBI Special Agent Tim "Sully" Sullivan. Sully was introduced in season 2 and worked alongside Brennan when Agent Seeley Booth (David Boreanaz) was away for therapy. The two eventually began dating as the show progressed.

McClintock first appeared in season 2's episode 13, titled "The Girl in the Gator." He was last seen in season 2's episode 16, titled "The Boneless Bride in the River.

With that being said, executive producer Michael Peterson told TV Line on what's in store for "Bones" Season 12. Peterson stated, "Sully might be bringing painful memories and some problems in his return in "Bones" Season 12. He, too, may cause trouble to the life of Brennan and Booth (David Boreanaz). "He comes back at a time in Brennan's life when she is emotionally unbalanced," She and Booth are going through a very difficult time."

Peterson further explained that Brennan and Booth are going through a rough patch, making it a "strange time" for Brennan and Sully's previous relationship to come up.

Sully and Brennan dated in season 2. As the latter is now having a problem with her relationship with Booth, she might make decisions in "Bones" Season 12 that might affect a lot of people.

As for the official plot synopsis of episode 3, Spoilers Guide notes, "When the body of an old man is found in an acid dump site, Booth, Brennan, and the squints find themselves deep in retirement home drama.

"Bones" Season 12 episode 3 is titled as "The New Tricks in the Old Dogs".