When human remains are discovered in the belly of a shark, Brennan and Booth are brought in to identify the missing person. Evidence suggesting the victim had been the prey of several fish directs the team's investigation to The Aquarium of the Atlantic, where a guest lecturer and notorious self-help guru preaching the healing power of the ocean has gone missing. Meanwhile, both Brennan and Booth navigate their own relationship when a marine biologist (guest star Rena Sofer) shows interest in Booth.