Air date: 2/7/07

When Booth is ordered to go see a psychiatrist after irrationally discharging his firearm (at the clown on the top of an ice cream truck), Brennan is paired up with Agent Tim Sullivan to investigate the apparent murder of a college student in the Everglades, and by the time the case is solved Sullivan and Brennan express their mutual interest in each other.

The Man in the Mansion

Air date: 2/14/07

When a benefactor of the Jeffersonian is found murdered, it's up to the team to find out who, but Hodgins' past with the widow complicates matters. Meanwhile Booth continues to see the therapist, and Brennan is progressing in her exploratory relationship with Sullivan.

The Bodies in the Book

Air date: 3/14/07

Three separate bodies are found murdered exactly the way Brennan wrote them in her new book. However, the killer's method was different every time, leading the team to believe that it was not one but three killers. Booth and Sully become concerned for Brennan, while she insists she can take care of herself. This increases tension between Sully and Brennan, straining their relationship. Booth tries to help them along, apparently fine with the couple. At the end of the episode, Sully and Brennan reconcile and Booth, walking away, looks back sadly.

The Boneless Bride in the River

Air date: 3/21/07

During Brennan's vacation, a woman's body is found with its bones removed. The team interviews people who knew the woman, but they all seemed to be hiding something. Meanwhile Sully tells Brennan he bought a boat and will be leaving for a year, at the end of the case, to give tours of the Caribbean. At the end of the episode Sully sails off in his new boat, "Temperance", while Brennan waves good-bye.