David Boreanaz, Emily Deschanel David Boreanaz, Emily Deschanel

Bones begins its eighth season with lots of unanswered questions, but there's one in particular that many of the show's characters must ask this season: Is love enough?

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"What we are trying to do this season is have everybody re-examining their relationships," executive producer Stephan Nathan tells TVGuide.com. "[Last season] everyone came together, everybody's relationships were solidified, and it was kind of a happy season. All of that got pulled apart at the end of the year, and now everybody is seeing the world in a new way."

The man behind that fracturing is serial killer Christopher Pelant (Andrew Leeds), who in the Season 7 finale used his hacking skills to frame Dr. Brennan (Emily Deschanel) for murder. Realizing the only way to fight Pelant was to go off the grid, Brennan took Baby Christine and went on the lam with her ex-con father (guest star Ryan O'Neal), leaving Booth (David Boreanaz) behind. On Monday's premiere (8/7c, Fox), a blonde (!) Brennan finally resurfaces, offering clues that will help her pals at the Jeffersonian both solve the murder  of a guidance counselor and perhaps prove her innocence.

But how will Booth react when he comes face-to-face with Brennan again? "When you haven't seen somebody for three months, you're terrified. You don't really know whether they're well, whether they're in danger, or how much danger they're in," Nathan says. "I think the initial reaction is relief and gratitude that [Brennan and Christine] are fine, and also just happiness that you're with this person that you love again."

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