Bones stars David Boreanaz and Emily Deschanel said fans can expect to see them put more of an effort into their relationship in season 9.

The duo, who play partners-turned-lovers Booth and Brennan, confirmed to TV Guide in a Monday interview that the couple would begin to rebuild their relationship in Monday's second episode. The episode features Booth and Brennan taking on a case at a couples retreat.

"There will be some progress by the second episode, but they're still not in a great place, and she doesn't know why he did what he did," Deschanel said, referring to the events of the season 8 finale.

Booth called off the wedding in the finale after the serial killer Pelant (Andrew Leeds) called him and threatened him to not marry Brennan or else five people would die.

Bones Season 9 Spoilers: 4:47 Mystery Solved & Freddie Prinze Jr. Character Against Booth/Brennan? [VIDEO]

"The exercises the two of them do at this retreat - a sweat lodge, an obstacle course - bring them a little bit closer to realizing how deeply rooted they are as a couple," Boreanaz added.

The mastermind fugitive Pelant will show up again in the season's fourth episode, Deschanel added. Both actors said the reason for introducing people from Booth's past in season 9 is to help him figure out a solution to his problem with Pelant.

Enstars previously reported that the couple will get married in episode 6, titled The Woman in White. Boreanaz and Deschanel discussed the possible locations for the honeymoon, throwing in South America and the Poconos.

Bones airs Mondays at 8 p.m. on Fox.

Watch a trailer for the second episode, titled The Cheat in the Retreat.

Tags: Bones Spoilers