Temperance Brennan
Portrayed by Emily Deschanel
Dr. Temperance Brennan works as a forensic anthropologist at the Jeffersonian Institute in Washington, D.C. and is also a best-selling novelist. Nicknamed "Bones" by FBI Special Agent Seeley Booth, Brennan and Booth work together in FBI cases concerning recently found human remains. Although she is an expert in her field, Brennan is socially awkward and has limited knowledge about pop culture.

Seeley Booth
Portrayed by David Boreanaz
Special Agent Seeley Booth is a former Army sniper with the Rangers, who is currently an agent with the FBI. He frequently consults with Dr. Brennan and her team in his investigations but prefers a more humane and interpersonal approach than Dr. Brennan's hard, objective and analytical approach. He is shown to be world-wise and socially at ease with people.

Angela Montenegro
Portrayed by Michaela Conlin
Angela Montenegro works as a forensic artist at the Jeffersonian Institute and is Dr. Brennan's best friend. Angela is Dr. Brennan team's specialist in forensic facial reconstruction and can generate holograms using her 3-dimensional graphics program to simulate various scenarios of a crime. She is open, friendly and caring, and constantly tries to draw Dr. Brennan out of the lab. In the episode "The Man in the Fallout Shelter", it was revealed that Angela's father is Billy Gibbons a member of the band ZZ Top.
During the aborted wedding between Angela and Hodgins that occurred in "Stargazer in a Puddle" it was revealed that Angela's middle name is Pearly Gates, which is also the name of the guitar played by Billy Gibbons

Zach Addy
Portrayed by Eric Millegan
Dr. Zach Addy is introduced as Dr. Brennan's graduate student and assistant at the Jeffersonian Institute at the start of the series. In the second season, he receives his doctorate in Forensic Anthropology and becomes a professional forensic anthropologist. Zach is as close to the stereotypical geek as anyone else on the team. Although well-meaning, helpful and friendly, when a situation calls for social interaction or intuition, he is often lost. During the course of events leading up to the death of Howard Epps, Zach was nearly killed after he unwittingly triggered a pressure sensor tied to a bomb affixed to the headless body of Caroline Epps.

In episode 2.22 "Stargazer in the Puddle" Zach reveals to Booth that the President of the United States requested that he undertake a mission to Iraq. Booth advised Zach to undertake the mission as revealed in the season three premiere episode, only to be sent home early due to an inability to assimilate to the team

Jack Hodgins
Portrayed by T. J. Thyne
Dr. Jack Hodgins is an entomologist, who is also an expert on spores and minerals, but conspiracy theories are his hobby. He is one of the more normal persons in the group, and helps teach Zach how to be socially normal. His family is extremely wealthy and Hodgins wishes for his current occupation to remain concealed from his family as he fears they will prevent him from pursuing his career.

Daniel Goodman (Season 1)
Portrayed by Jonathan Adams
Dr. Daniel Goodman is a former archaeologist turned administrator, who is also the director of the Jeffersonian Institute. He is a loving husband and father to a pair of five-year-old twin girls. His way of working leads Hodgins to think of him as subjective and long winded, and lacking the qualities of a pure scientist, although the antagonism between the two develops into a friendly rivalry as the series progresses. He has not made any appearances beyond the first season. As of Episode 2.1 "The Titan on the Tracks" Dr. Goodman is said to be on a sabbatical.

Camille Saroyan
Portrayed by Tamara Taylor
Dr. Camille Saroyan is the Head of the Forensic Division at Jeffersonian Institute. She was introduced in the first episode of the second season after being hired by Dr. Goodman while Dr. Brennan was on vacation. She was born in The Bronx and was a coroner in New York before taking up the position at the Jeffersonian. At the beginning of the second season, she and Dr. Brennan have an uneasy working relationship due to her being Dr. Brennan's superior and their different work styles. Dr. Saroyan had a romantic relationship with Booth prior to her joining the Jeffersonian. This relationship was briefly rekindled until Dr. Saroyan almost died after being poisoned by serial killer Howard Epps in the episode "The Man in the Cell" and Booth realized that his "high risk" life put anyone close to him in danger.

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Writer: Hart Hanson

Director: Greg Yaitanes

StoryM: Kathy Reichs

Guest Stars: John M. Jackson (FBI Deputy Director Sam Cullen (uncredited)), Marilyn Sue Perry (Customs Agent), Charles Janasz (Reverend), Naja Hill (Cleo Eller), Tyrees Allen (Ted Eller), Sam Trammell (Ken Thompson), Larry Poindexter (Sen. Bethlehem), Chris Conner (Oliver Laurier), Dominic Fumusa (Peter St. James), Katherine Ann McGregor (Mrs. Bethlehem), Dave Roberson (Homeland Security), John Sterling Carter (FBI Director), Bonita Friedericy (Sharon Eller), Damian T. Raven (Uniformed Security), Yun Choi (FBI Agent #1), Jeff Witzke (FBI Agent #2), Billy Briggs (Airport Clerk)

Summary
Having just spent two months in Guatemala where she was identifying victims of genocide, renowned forensic anthropologist Dr. Temperance Brennan returns to Washington, D.C., where she is immediately detained by an agent from Homeland Security for carrying a human skull in her bag. Upon the arrival of FBI Special Agent Seeley Booth, Brennan is released, which she finds odd and realizes that it was his ploy to get her to help him on an FBI case. She refuses to help until Booth promises her full participation in the case, which he reluctantly does.

At the crime scene, Brennan and Booth find human remains which were so thoroughly decomposed that only the bones remained. Brennan and her assistant, Zack Addy (Eric Millegan), determine the victim is a woman between 18 to 23 years old, and was a tennis player. Back at the Jeffersonian Institute, Brennan argues with her boss, Dr. Daniel Goodman, who feels no qualms about assigning her to work with other federal agencies without her permission.

Inside the Medico-Legal Lab of the Jeffersonian Institute, Brennan examines the victim's remains while her colleagues inquire about the resemblances between them and the characters in her new book, Bred in the Bone. Dr. Jack Hodgins (T. J. Thyne), an entomologist, tells Brennan that the victim has been in the pond for more than two summers. Hodgins has also found small bone fragments in the silt, which he guesses are rana temporaria or simply, frog bones. Angela Montenegro (Michaela Conlin), a forensic artist, uses a computer program she has developed, called the Angelator, to make a three dimensional holographic reconstruction of the skull, which Brennan reassembled. The identity of the victim is revealed to be Cleo Louise Eller, who was a missing senate intern and was rumored to have had an affair with Senator Bethlehem.

Brennan wants to confront the Senator but Booth argues that the Senator is not the only suspect. The Senator's aide, Ken Thompson, was Cleo's boyfriend. There is also Cleo's stalker, Oliver Laurier. Booth tells Brennan that they have a major case and that FBI Deputy Director Cullen is going to want to set up a special unit to investigate, which means they are going to have do things by the book and wants her to stay at her lab. Brennan blackmails Booth until he agrees to let her come with him into the field.

Based on the particulates embedded in Cleo's skull, Hodgins determines that Cleo's skull may have been smashed by a sledgehammer on a cement floor and diatomaceous earth. By the distinctive damage done to her finger pads and the way the body was hidden, the team determines that the murderer had put a lot of effort into hiding the victim. Hodgins also reveals that Cleo was taking medicine for her depression, while Brennan realizes that the small bones found with Cleo's body are not frog bones but fetal ear bones, indicating Cleo Eller was pregnant.

Hodgins, a conspiracy theorist, convinces Brennan that they may never find the truth as Senator Bethlehem may have enough power to impede the investigation. Without telling Booth, Brennan decides to confront the Senator. Consequently, Deputy Director Cullen removes Booth from the case but Brennan refuses to give up. With the help of her fellow scientists, she uncovers that Cleo Eller's boyfriend Ken Thompson, had killed Cleo because he feared the scandal Cleo's pregnancy would cause and affect his career.

Matthew Brennan/Max Keenan (Season 2 -)
Portrayed by Ryan O'Neal
Max is the father of Temperance and Russ Brennan. He took the identity of a deceased Matthew Brennan and changed the identities of his family to protect them from the violent bank robbers who he and his wife worked with as career criminals. As Matthew Brennan, he worked as a science teacher while his wife worked as a bookkeeper. In Christmas of 1991, Max and his wife left their children alone and never returned to their home in order to keep them safe. After Dr. Brennan solved the murder of her mother, he warned her to stop looking for him. When Russ became the target of corrupted FBI agents, Max was forced to resurface and to kill the men. Max resurfaces a second time during the episode "The Killer in the Concrete" when Dr. Brennan asks for his help to find Booth who was kidnapped during the course of the investigation. After freeing Booth Max escapes in Dr. Brennan's car. Max was later arrested by Booth at the conclusion of "Stargazer in a Puddle."

Russ Brennan/Kyle Keenan (Season 1 -)
Portrayed by Loren Dean
Russ is Temperance Brennan's brother, who left her when she was fifteen years old and he was nineteen years old, immediately after the disappearance of their parents. At seven years old, his father told him that he was never to use the name Kyle Keenan again and that his new name was Russ Brennan. When they were children, he had a close relationship with his baby sister, Temperance Brennan, who idolized him. After he left home, Russ committed various misdemeanors and felonies. He worked as a mechanic in North Carolina, however, after his father resurfaced, he went into hiding with him and has not had contact with Temperence.

Sam Cullen (Season 1)
Portrayed by John M. Jackson
Sam Cullen is a Deputy Director of the FBI. Very little info is known about him, other than he has a wife and also a daughter diagnosed with terminal lung cancer. The episode "The Graft in the Girl" revealed that she contracted the disease from an illegally sourced bone graft; Brennan and Booth discovered and arrested the criminal responsible. He does his best to keep Agent Booth on track and frequently disapproves of Dr. Brennan's involvement in FBI field investigations.

Howard Epps (Season 1 - 2)
Portrayed by Heath Freeman
Howard Epps is a serial killer, who appeared in one episode of the first season and two episodes of the second season. Epps was introduced in the episode, "A Man on Death Row", where he was a prisoner scheduled to be executed in two days, while his lawyer enlisted Brennan and Booth to try and clear his name. They were successful in delaying his execution pending a further review of the evidence, but realized too late that he was guilty. While in prison, he began a relationship with (and married) a woman named Caroline, who knew he was guilty, but believed him to be a good person underneath it all. Most of his victims were blonde teenage girls.
Epps' second appearance was in episode "The Blonde in the Game", where he is still in jail, but has been directing an accomplice to continue his crimes in his absence, leaving clues for Brennan and the team to solve to lead them to the next victims. When Brennan and Booth corner the accomplice, Brennan is forced to shoot him to save the lives of Booth and the final victim. When questioned, Epps reveals that the objective of "the game" was to force Brennan to kill, something she has never done before. As Epps had planned, Brennan feels deeply guilty for killing the man, but she eventually comes to terms with it.
In his final appearance of the series, "The Man in the Cell", Epps successfully escapes from prison during a fire by killing a fireman, stealing his uniform and leaving his body is his own cell. After his escape, he becomes obsessed with Brennan, using mind games to and make her feel like she was responsible for the deaths of his victims. He tests her and the rest of her team by leaving clues for them to discover and decipher that lead them to more victims, one of whom was his wife, Caroline. He also leave traps in the clues, almost killing Zach in an explosion and Dr. Saroyan when she inhales a deadly toxin hidden in Caroline's head. After being cornered in Brennan's apartment by her and Booth, he runs for the balcony but falls off the balcony to his death.

Caroline Julian (Season 1 -)
Portrayed by Patricia Belcher
Caroline Julian is a prosecutor and works as in the U.S. Attorney's office. Her first appearance was in the first season episode, "The Man in the Morgue", which was followed by three more appearances in the second season in "Judas on a Pole", "The Man in the Mansion" and "Stargazer in a Puddle". She has a very demanding and bossy attitude, which overpowers even Brennan to a point where Brennan does not even argue with her. She has a deep understanding in the workings of the government and the way cases should be handled, she seems to have a friendship history with Booth and trusts in his instincts and beliefs when working on cases, although she often seems weary of their less orthodox methods. She has appeared numerous times to have Booth and Brennan in court and to solve their cases.

Oliver Laurier (Season 1 -)
Portrayed by Chris Conner
Oliver Laurier's first appearance in the series is in the pilot episode as a suspect in the murder of Cleo Louise Eller, who he was obsessed with. Towards the end of the episode, Oliver becomes obsessed with Dr. Brennan, who he stalks from scene to scene. His next appearance was in the second season's episode, "Bodies in the Book", where he is again suspected of murder. He confesses to being a "Brennanite", a loyal fan of Dr. Brennan's crime novels, but was proved not to be the killer.

Tim Sullivan (Season 2)
Portrayed by Eddie McClintock
Special Agent Tim "Sully" Sullivan is an FBI agent introduced in the second season to be Dr. Brennan's love interest. He makes four consecutive appearances in the second season starting with episode "The Girl in the Gator", where he works with Dr. Brennan in a case while Booth was in therapy. Brennan doubted his sincerity at first because of his wide variety of interests and hobbies, but Booth assured her that Sully is serious about his job and mentions that he had previously lost his partner. After working on the case, Sully asks Brennan out on a date, which she eagerly agreed to. Their relationship becomes more serious and in episode "The Boneless Bride In The River", Sully asks Brennan to go with him to the Caribbean in his new boat which he named after her, but she refuses. He tells Brennan that he will come back in a year's time.

Gordon Wyatt (Season 2)
Portrayed by Stephen Fry
Dr. Wyatt is the psychiatrist trained in forensic psychology and who was assigned to evaluate Agent Seeley Booth in the episode "The Girl in the Gator" after Booth shoots at an ice cream truck. At first, Booth regards his therapy with skepticism but eventually comes to befriend Dr. Wyatt. According to Booth, Dr. Wyatt is "so English". Dr. Wyatt also became involved in the lives of the "squints" in episode "The Priest in the Churchyard", when Booth asked Brennan to come to therapy with him to work out some partnership problems. Temperance, who has repeatedly shown an aversion to psychology, seems to have taken a liking to Dr. Wyatt because what he says makes sense so much so that she even takes Angela to see him when Angela is unsure of how to respond to Hodgins' request for her to move in with him.

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