With the season nine premiere of Fox's popular crime-solving drama "Bones" just a few weeks away, fans are eager to find out what to expect in the upcoming season. Choice details have emerged about the pending nuptials between Booth (David Boreanaz) and Brennan (Emily Deschanel), as well as some guest casting news. Now some details about the show's other cast members are coming to light.

Executive producer Stephen Nathan spoke to Entertainment Weekly to discuss some interesting details about the upcoming ninth season. As previously reported, actor Freddie Prinze Jr. has been tapped to play Danny, "a very covert CIA agent" who happens to be an old colleague of Booth's. Nathan explained that the two will find themselves at odds while working the same case but on opposite sides.

The situation will allow fans to "see their friendship and relationship but also see the tension that exists between them because they're operating from different sides," Nathan teased. According to EW, while the premiere will be the first episode Prinze Jr. appears in, it won't be the last.

Meanwhile, actor John Francis Daley, who plays Dr. Sweets, revealed to TVLine that his character will question whether or not he "wants to keep dong what he's doing at the FBI." Daley said, "No matter how hard he tries, he doesn't feel like he's making enough of a difference in the world. Profiling criminals wasn't the reason he got into his profession in the first place. So this season will definitely explore that inner monologue that's going on with him."

TVLine reported that the young psychologist's "soul searching" will lead him away from his work at the Jeffersonian. Daley explained, "There's an opportunity for him to do something completely different, and he tries it out. And somehow it leads to a lot of guns being shot and a lot of drama in the interrogation room. It's chaos!"

Of course, Sweets won't be the only one having some interesting revelations this season. According to Nathan, Dr. Hodgins (T.J. Thyne) will discover that his family history is "far more involved than he ever thought." The EP revealed to EW, "A bill comes due that he never thought he had, but it had always been paid by the estate. Now, it comes to him and the bill is for a situation he could have ever envisioned."

Nathan also spilled on what fans can expect will be revealed this season. "This season we are going to answer many of the questions that have plagued us and the audience for some time," he said. "We're going to be looking at 4:47, the clock mystery. Perhaps we're even going to find out what Brennan wrote to Booth when she was buried alive. Lots of character mysteries will be resolved this season."

"Bones" returns for season 9 on Monday, September 16 at 8 p.m. on Fox. On November 8, the show moves to its new Friday at 8 p.m. time slot.