After a skull smashes into the windshield of a teenager's car, the investigation reveals the skull has been gnawed on by human teeth, which implies cannibalism and marks the beginning of the Widow's Son case. Meanwhile, Angela and Hodgins hire a private investigator to find her husband. Bones searches for Zach's replacement and the team gets a wonderful surprise.

Brennan and Booth investigate the death of a soccer mom who was blown up in her mini-van. They soon discover that the victim was part of a group of radicals from the 70's, adding several names to the list of possible suspects.

Things get kinky when Booth and Brennan follow murder clues that lead to a lodge used as an S&M retreat for "jockeys" and their "horses." Meanwhile, Angela tries hypnosis in an effort to figure out her elusive husband's name so she can finally divorce him.